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Research Article On -Gamma and -Beta Distributions and Moment Generating Functions Gauhar Rahman, Shahid Mubeen, Abdur Rehman, and Mammona Naz Department of Mathematics, University of Sargodha, Sargodha 40100, Pakistan Correspondence should be addressed to Gauhar Rahman; [email protected] Received 10 February 2014; Revised 29 June 2014; Accepted 4 July 2014; Published 15 July 2014 Academic Editor: Chin-Shang Li Copyright © 2014 Gauhar Rahman et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. e main objective of the present paper is to define -gamma and -beta distributions and moments generating function for the said distributions in terms of a new parameter >0. Also, the authors prove some properties of these newly defined distributions. 1. Basic Definitions In this section we give some definitions which provide a base for our main results. e definitions (1.11.3) are given in [1] while (1.41.6) are introduced in [2]. Also, we have taken some statistics related definitions (1.71.11) from [35]. 1.1. Pochhmmer Symbol. e factorial function is denoted and defined by () ={ ( + 1) ( + 2) ⋅ ⋅ ⋅ ( + − 1) ; for ≥ 1, ̸ = 0, 1; if = 0. (1) e function () defined in relation (1) is also known as Pochhmmer symbol. 1.2. Gamma Function. Let C; the Euler gamma function is defined by Γ () = lim →∞ ! −1 () (2) and the integral form of gamma function is given by Γ () = ∫ 0 −1 , R () > 0. (3) From the relation (3), using integration by parts, we can easily show that Γ ( + 1) = Γ () . (4) e relation between Pochhammer symbol and gamma function is given by () = Γ ( + ) Γ () . (5) 1.3. Beta Function. e beta function of two variables is defined as (, ) = ∫ 1 0 −1 (1 − ) −1 , Re () , Re () > 0 (6) and, in terms of gamma function, it is written as (, ) = Γ () Γ () Γ ( + ) . (7) 1.4. Pochhammer -Symbol. For >0, the Pochhammer - symbol is denoted and defined by () , ={ ( + ) ( + 2) ⋅ ⋅ ⋅ ( + ( − 1) ) ; for ≥ 1, ̸ = 0, 1; if = 0. (8) Hindawi Publishing Corporation Journal of Probability and Statistics Volume 2014, Article ID 982013, 6 pages http://dx.doi.org/10.1155/2014/982013
Transcript
Page 1: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

Research ArticleOn 119896-Gamma and 119896-Beta Distributions andMoment Generating Functions

Gauhar Rahman Shahid Mubeen Abdur Rehman and Mammona Naz

Department of Mathematics University of Sargodha Sargodha 40100 Pakistan

Correspondence should be addressed to Gauhar Rahman gauhar55uomgmailcom

Received 10 February 2014 Revised 29 June 2014 Accepted 4 July 2014 Published 15 July 2014

Academic Editor Chin-Shang Li

Copyright copy 2014 Gauhar Rahman et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The main objective of the present paper is to define 119896-gamma and 119896-beta distributions and moments generating function for thesaid distributions in terms of a new parameter 119896 gt 0 Also the authors prove some properties of these newly defined distributions

1 Basic Definitions

In this section we give some definitions which provide a basefor our main results The definitions (11ndash13) are given in[1] while (14ndash16) are introduced in [2] Also we have takensome statistics related definitions (17ndash111) from [3ndash5]

11 Pochhmmer Symbol Thefactorial function is denoted anddefined by

(119886)119899=

119886 (119886 + 1) (119886 + 2) sdot sdot sdot (119886 + 119899 minus 1) for 119899 ge 1 119886 = 0

1 if 119899 = 0

(1)

The function (119886)119899defined in relation (1) is also known as

Pochhmmer symbol

12 Gamma Function Let 119911 isin C the Euler gamma functionis defined by

Γ (119911) = lim119899rarrinfin

119899119899119911minus1

(119911)119899

(2)

and the integral form of gamma function is given by

Γ (119911) = int

infin

0

119905119911minus1

119890minus119905

119889119905 R (119911) gt 0 (3)

From the relation (3) using integration by parts we can easilyshow that

Γ (119911 + 1) = 119911Γ (119911) (4)The relation between Pochhammer symbol and gammafunction is given by

(119911)119899=Γ (119911 + 119899)

Γ (119911) (5)

13 Beta Function The beta function of two variables isdefined as

119861 (119909 119910) = int

1

0

119905119909minus1

(1 minus 119905)119910minus1

119889119905 Re (119909) Re (119910) gt 0 (6)

and in terms of gamma function it is written as

119861 (119909 119910) =Γ (119909) Γ (119910)

Γ (119909 + 119910) (7)

14 Pochhammer 119896-Symbol For 119896 gt 0 the Pochhammer 119896-symbol is denoted and defined by

(119886)119899119896

= 119886 (119886 + 119896) (119886 + 2119896) sdot sdot sdot (119886 + (119899 minus 1) 119896) for 119899 ge 1 119886 = 0

1 if 119899 = 0

(8)

Hindawi Publishing CorporationJournal of Probability and StatisticsVolume 2014 Article ID 982013 6 pageshttpdxdoiorg1011552014982013

2 Journal of Probability and Statistics

15 119896-Gamma Function For 119896 gt 0 and 119911 isin C the 119896-gammafunction is defined as

Γ119896(119911) = lim

119899rarrinfin

119899119896119899

(119899119896)119911119896minus1

(119911)119899119896

(9)

and the integral representation of 119896-gamma function is

Γ119896(119911) = int

infin

0

119905119911minus1

119890minus119905119896119896

119889119905 (10)

16 119896-Beta Function For Re(119909)Re(119910) gt 0 the 119896-betafunction of two variables is defined by

119861119896(119909 119910) =

1

119896int

infin

0

119905119909119896minus1

(1 minus 119905)119910119896minus1

119889119905 (11)

and in terms of 119896-gamma function 119896-beta function is definedas

119861119896(119909 119910) =

Γ119896(119909) Γ119896(119910)

Γ119896(119909 + 119910)

(12)

Also the researchers [6ndash10] have worked on the gen-eralized 119896-gamma and 119896-beta functions and discussed thefollowing properties

Γ119896(119909 + 119896) = 119909Γ

119896(119909) (13)

(119909)119899119896

=Γ119896(119909 + 119899119896)

Γ119896(119909)

(14)

Γ119896(119896) = 1 119896 gt 0 (15)

Using the above relations we see that for 119909 119910 gt 0 and 119896 gt

0 the following properties of 119896-beta function are satisfied byauthors (see [6 7 11])

120573119896(119909 + 119896 119910) =

119909

119909 + 119910120573119896(119909 119910) (16)

120573119896(119909 119910 + 119896) =

119910

119909 + 119910120573119896(119909 119910) (17)

120573119896(119909119896 119910119896) =

1

119896120573 (119909 119910) (18)

120573119896(119909 119896) =

1

119909 120573

119896(119896 119910) =

1

119910 (19)

Note that when 119896 rarr 1 120573119896(119909 119910) rarr 120573(119909 119910)

For more details about the theory of 119896-special functionslike 119896-gamma function 119896-beta function 119896-hypergeometricfunctions solutions of 119896-hypergeometric differential equa-tions contegious functions relations inequalities with appli-cations and integral representations with applications involv-ing 119896-gamma and 119896-beta functions and so forth (See [12ndash17])

17 Probability Distribution and Expected Values In a ran-dom experiment with 119899 outcomes suppose a variable 119883

assumes the values 1199091 1199092 1199093 119909

119899with corresponding

probabilities 1198751 1198752 1198753 119875

119899 then this collection is called

probability distribution andΣ119901119894= 1 (in case of discrete distri-

butions) Also if119891(119909) is a continuous probability distributionfunction defined on an interval [119886 119887] then int119887

119886

119891(119909)119889119909 = 1In statistics there are three types of moments which are

(i) moments about any point 119909 = 119886 (ii) moments about119909 = 0 and (iii) moments about mean position of the givendata Also expected value of the variate is defined as the firstmoment of the probability distribution about 119909 = 0 and the119903th moment about mean of the probability distribution isdefined as 119864(119909

119894minus 119909)119903 where 119909 is the mean of the distribution

Also 119864(119909) shows the expected value of the variate 119909 andis defined as the first moment of the probability distributionabout 119909 = 0 that is

1205831015840

1= 119864 (119909) = int

119887

119886

119909119891 (119909) 119889119909 (20)

18 GammaDistribution A continuous random variable119885 issaid to have a gamma distribution with parameter 119898 gt 0 ifits probability distribution function is defined by

119891 (119911) =

1

Γ (119898)119911119898minus1

119890minus119911

0 ≦ 119911 lt infin

0 elsewhere(21)

and its distribution function 119865(119911) is defined by

119865 (119911) =

int

119911

0

1

Γ (119898)119911119898minus1

119890minus119911

119889119911 119911 ge 0

0 119911 lt 0

(22)

which is also called the incomplete gamma function

19 Moment Generating Function of Gamma DistributionThemoment generating function of 119885 is defined by

1198720(119905) = 119864 (119890

119905119885

) = int

infin

0

119890119905119885

119891 (119911) 119889119911

= int

infin

0

1

Γ (119898)119911119898minus1

119890minus119911(1minus119905)

119889119911

(23)

110 Beta Distribution of the First Kind A continuous ran-dom variable 119885 is said to have a beta distribution with twoparameters119898 and 119899 if its probability distribution function isdefined by

119891 (119911) =

1

119861 (119898 119899)119911119898minus1

(1 minus 119911)119899minus1

0 ≦ 119911 ≦ 1 119898 119899 gt 0

0 elsewhere(24)

Journal of Probability and Statistics 3

This distribution is known as a beta distribution of the firstkind and a beta variable of the first kind is referred to as1205731(119898 119899) Its distribution function 119865(119911) is given by

119865 (119911)

=

0 119911 lt 0

int

119911

0

1

119861 (119898 119899)119911119898minus1

(1 minus 119911)119899minus1

119889119911 0 ≦ 119911 ≦ 1 119898 119899 gt 0

0 119911 gt 1

(25)

111 Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891 (119911) =

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

0 ≦ 119911 lt infin 119898 119899 gt 0

0 otherwise(26)

and its probability distribution function is given by

119865 (119911) = int

infin

0

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

119889119911 0 ≦ 119911 lt infin 119898 119899 gt 0

(27)

2 Main Results 119896-Gamma and119896-Beta Distributions

In this section we define gamma and beta distributions interms of a new parameter 119896 gt 0 and discuss some propertiesof these distributions in terms of 119896

Definition 1 Let 119885 be a continuous random variable then itis said to have a 119896-gamma distributionwith parameters119898 gt 0

and 119896 gt 0 if its probability density function is defined by

119891119896(119911) =

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

0 ≦ 119911 lt infin 119896 gt 0

0 elsewhere(28)

and its distribution function 119865119896(119911) is defined by

119865119896(119911) =

int

119911

0

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

119889119911 119911 gt 0

0 119911 lt 0

(29)

Proposition 2 The newly defined Γ119896(119898) distribution satisfies

the following properties

(i) The 119896-gamma distribution is the probability distribu-tion that is area under the curve is unity

(ii) The mean of 119896-gamma distribution is equal to aparameter119898

(iii) The variance of 119896-gamma distribution is equal to theproduct of two parameters119898119896

Proof of (i) Using the definition of 119896-gamma distributionalong with the relation (10) we have

int

infin

0

119891119896(119911) 119889119911 =

1

Γ119896(119898)

int

infin

0

119911119898minus1

119890minus119911119896119896

119889119911 =Γ119896(119898)

Γ119896(119898)

= 1

(30)

Proof of (ii) Asmean of a distribution is the expected value ofthe variate so the mean of the 119896-gamma distribution is givenby

119911 = 119864119896(119885) =

1

Γ119896(119898)

int

infin

0

119911 sdot 119911119898minus1

119890minus119911119896119896

119889119911 (31)

Using the definition of 119896-gamma function and the relation(13) we have

119911 =1

Γ119896(119898)

int

infin

0

119911119898

119890minus119911119896119896

119889119911 =Γ119896(119898 + 119896)

Γ119896(119898)

= 119898Γ119896(119898)

Γ119896(119898)

= 119898

(32)

Proof of (iii) As variance of a distribution is equal to 119864(1199092) minus(119864(119909))

2 so the variance of 119896-gamma distribution is calculatedas

Var119896(119885) = 119864

119896(1198852

) minus (119864119896(119885))2

(33)

Now we have to find 119864119896(1198852

) which is given by

119864119896(1198852

) =1

Γ119896(119898)

int

infin

0

1199112

sdot 119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898+1

119890minus119911119896119896

119889119911

=Γ119896(119898 + 2119896)

Γ119896(119898)

=(119898 + 119896)119898Γ

119896(119898)

Γ119896(119898)

= 119898 (119898 + 119896)

(34)

Thus we obtain the variance of 119896-gamma distribution as

1205902

119896= 119898 (119898 + 119896) minus 119898

2

= 119898119896 (35)

where 1205902119896is the notation of variance present in the literature

21 119896-Beta Distribution of First Kind Let 119885 be a continuousrandom variable then it is said to have a 119896-beta distributionof the first kindwith two parameters119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

0 ≦ 119911 ≦ 1 119898 119899 119896 gt 0

0 elsewhere(36)

4 Journal of Probability and Statistics

In the above distribution the beta variable of the first kind isreferred to as 120573

1119896(119898 119899) and its distribution function 119865

119896(119911) is

given by

119865119896(119911) =

0 119911 lt 0

int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911 0 ≦ 119911 ≦ 1

119898 119899 gt 0

0 119911 gt 1

(37)

Proposition 3 The 119896-beta distribution 1205731119896(119898 119899) satisfies the

following basic properties

(i) 119896-beta distribution is the probability distribution thatis the area of 120573

1119896(119898 119899) under a curve 119891

119896(119911) is unity

(ii) The mean of this distribution is119898(119898 + 119899)(iii) The variance of 120573

1119896(119898 119899) is119898119899119896((119898+119899)

2

(119898+119899+119896))

Proof of (i) By using the above definition of 119896-beta distribu-tion we have

int

119911

0

119865119896(119911) 119889119911 = int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(38)

By the relation (11) we get

int

119911

0

119865119896(119911) 119889119911 = int

1

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 119899)

119861119896(119898 119899)

= 1

(39)

Proof of (ii) Themean of the distribution 12058310158401119896 is given by

1205831015840

1119896= 119864119896(119885) = int

119911

0

119911119865119896(119911) 119889119911

= int

119911

0

1

119896119861119896(119898 119899)

119911 sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(40)

Using the relations (12) (13) and (16) we have

1205831015840

1119896= int

1

0

1

119896119861119896(119898 119899)

119911119898119896

(1 minus 119911)119899119896minus1

119889119911 =119861119896(119898 + 119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 119896)

=119898

119898 + 119899

(41)

Proof of (iii) The variance of 1205731119896(119898 119899) is given by

1205902

119896= (Var)

119896= 119864119896(1198852

) minus (119864119896(119885))2

(42)

119864119896(1198852

) = int

1

0

1

119896119861119896(119898 119899)

119911119898119896+1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 2119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 2119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 2119896)

=119898 (119898 + 119896)

(119898 + 119899) (119898 + 119899 + 119896)

(43)

Thus substituting the values of119864119896(1198852

) and119864119896(119885) in (42) along

with some algebraic calculations we have the desired result

22 119896-Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a 119896-beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

0 ≦ 119911 lt infin 119898 119899 119896 gt 0

0 otherwise(44)

Note The 119896-beta distribution of the second kind is denotedby 1205732119896(119898 119899)

Theorem 4 The 119896-beta function of the second kind representsa probability distribution function that is

int

infin

0

119891119896(119911) 119889119911 = 1 (45)

Proof We observe that

int

infin

0

119891119896(119911) 119889119911 = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

119889119911 (46)

Let 1 + 119911 = 1119910 so that 119889119911 = minus1198891199101199102 thus by using the

relation (11) the above equation gives

=1

120573119896(119898 119899)

1

119896int

1

0

119910119899119896minus1

(1 minus 119910)119898119896minus1

119889119910 =120573119896(119898 119899)

120573119896(119898 119899)

= 1

(47)

3 Moment Generating Function of119896-Gamma Distribution

In this section we derive the moment generating functionof continuous random variable 119885 of newly defined 119896-gamma

Journal of Probability and Statistics 5

distribution in terms of a new parameter 119896 gt 0 which isillustrated as

1198720119896(119905) = 119864

119896(119890119905119885119896

) = int

infin

0

1

Γ119896(119898)

119890119905119911119896

119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898minus1

119890(minus119911119896119896)(1minus119896119905)

119889119911

(48)

Let 119906 = 119911(1minus119896119905)1119896 so that 119911 = 119906(1minus119896119905)

1119896 and 119889119911 = 119889119906(1minus

119896119905)1119896 Then substituting these values in (48) we obtain

1198720119896(119905) =

1

(1 minus 119896119905)(119898minus1)119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

(1 minus 119896119905)1119896

=1

(1 minus 119896119905)119898119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

=Γ119896(119898)

(1 minus 119896119905)119898119896

Γ119896(119898)

= (1 minus 119896119905)minus119898119896

|119896119905| lt 1

(49)

Now differentiating 119903 times 1198720119896(119905) with respect to 119905 and

putting 119905 = 0 we get

1205831015840

119903119896= 119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896) (50)

Thus when 119903 = 1 we obtain 1205831015840

1119896= 119898 when 119903 = 2 1205831015840

2119896=

119898(119898+ 119896) and hence 1205832119896

= 12058310158402

1119896minus 1205831015840

2119896= 119898119896 = variance of the

119896-gamma distribution proved in Proposition 2

31 Higher Moment in terms of 119896 The 119903th moment in termsof 119896 is given by

1205831015840

119903119896

= 119864 (119885119903

) =1

119896119861119896(119898 119899)

int

1

0

119911119903

sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=1

119896119861119896(119898 119899)

int

1

0

119911119898119896+119903minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 119903119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119898 + 119903119896 + 119899)

=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119898 + 119899) (119898 + 119899 + 119896) (119898 + 119899 + 2119896) sdot sdot sdot (119898 + 119899 + (119903 minus 1) 119896)

(51)

Theorem 5 The moments of the higher order of 119896-betadistribution of the second kind are given as

1205831015840

119903119896=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119899 minus 119896) (119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) (52)

Proof Consider

1205831015840

119903119896= 119864 (119885

119903

) = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1+119903

(1 + 119911)(119898+119899)119896

119889119911 (53)

Changing the variables as 119911 = (1 minus 119910)119910 rArr 119889119911 = (minus11199102

)119889119910above equation becomes

=1

119896120573119896(119898 119899)

int

1

0

119910119899119896minus119903minus1

(1 minus 119910)119898119896+119903minus1

119889119910 (54)

Replacing (1 minus 119910) by 119905 we have

1205831015840

119903119896=

1

120573119896(119898 119899)

1

119896int

1

0

119905119898119896+119903minus1

(1 minus 119905)119899119896minus119903minus1

119889119905

=120573119896(119898 + 119903119896 119899 minus 119903119896)

120573119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896)

Γ119896(119898) Γ119896(119899)

(55)

Now using Γ119896(119899 minus 119903119896) = Γ

119896(119899)(119899 minus 119896)(119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) in

the above equation we get the desired result

4 Conclusion

In this paper the authors conclude that we have the following

(i) If 119896 tends to 1 then 119896-gamma distribution and 119896-beta distribution tend to classical gamma and betadistribution

(ii) The authors also conclude that the area of 119896-gammadistribution and 119896-beta distribution for each positivevalue of 119896 is one and theirmean is equal to a parameter119898 and 119898(119898 + 119899) respectively The variance of 119896-gamma distribution for each positive value of 119896 isequal to 119896 times of the parameter 119898 In this case if119896 = 1 then it will be equal to variance of gammadistribution The variance of 119896-beta distribution foreach positive value of 119896 is also defined

(iii) In this paper the authors introduced moments gener-ating function and higher moments in terms of a newparameter 119896 gt 0

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to express profound gratitude toreferees for deeper review of this paper and the refereersquos usefulsuggestions that led to an improved presentation of the paper

References

[1] E D Rainville Special Functions The Macmillan New YorkNY USA 1960

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

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Differential EquationsInternational Journal of

Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Mathematical PhysicsAdvances in

Complex AnalysisJournal of

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OptimizationJournal of

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CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Operations ResearchAdvances in

Journal of

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Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

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Discrete Dynamics in Nature and Society

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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 2: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

2 Journal of Probability and Statistics

15 119896-Gamma Function For 119896 gt 0 and 119911 isin C the 119896-gammafunction is defined as

Γ119896(119911) = lim

119899rarrinfin

119899119896119899

(119899119896)119911119896minus1

(119911)119899119896

(9)

and the integral representation of 119896-gamma function is

Γ119896(119911) = int

infin

0

119905119911minus1

119890minus119905119896119896

119889119905 (10)

16 119896-Beta Function For Re(119909)Re(119910) gt 0 the 119896-betafunction of two variables is defined by

119861119896(119909 119910) =

1

119896int

infin

0

119905119909119896minus1

(1 minus 119905)119910119896minus1

119889119905 (11)

and in terms of 119896-gamma function 119896-beta function is definedas

119861119896(119909 119910) =

Γ119896(119909) Γ119896(119910)

Γ119896(119909 + 119910)

(12)

Also the researchers [6ndash10] have worked on the gen-eralized 119896-gamma and 119896-beta functions and discussed thefollowing properties

Γ119896(119909 + 119896) = 119909Γ

119896(119909) (13)

(119909)119899119896

=Γ119896(119909 + 119899119896)

Γ119896(119909)

(14)

Γ119896(119896) = 1 119896 gt 0 (15)

Using the above relations we see that for 119909 119910 gt 0 and 119896 gt

0 the following properties of 119896-beta function are satisfied byauthors (see [6 7 11])

120573119896(119909 + 119896 119910) =

119909

119909 + 119910120573119896(119909 119910) (16)

120573119896(119909 119910 + 119896) =

119910

119909 + 119910120573119896(119909 119910) (17)

120573119896(119909119896 119910119896) =

1

119896120573 (119909 119910) (18)

120573119896(119909 119896) =

1

119909 120573

119896(119896 119910) =

1

119910 (19)

Note that when 119896 rarr 1 120573119896(119909 119910) rarr 120573(119909 119910)

For more details about the theory of 119896-special functionslike 119896-gamma function 119896-beta function 119896-hypergeometricfunctions solutions of 119896-hypergeometric differential equa-tions contegious functions relations inequalities with appli-cations and integral representations with applications involv-ing 119896-gamma and 119896-beta functions and so forth (See [12ndash17])

17 Probability Distribution and Expected Values In a ran-dom experiment with 119899 outcomes suppose a variable 119883

assumes the values 1199091 1199092 1199093 119909

119899with corresponding

probabilities 1198751 1198752 1198753 119875

119899 then this collection is called

probability distribution andΣ119901119894= 1 (in case of discrete distri-

butions) Also if119891(119909) is a continuous probability distributionfunction defined on an interval [119886 119887] then int119887

119886

119891(119909)119889119909 = 1In statistics there are three types of moments which are

(i) moments about any point 119909 = 119886 (ii) moments about119909 = 0 and (iii) moments about mean position of the givendata Also expected value of the variate is defined as the firstmoment of the probability distribution about 119909 = 0 and the119903th moment about mean of the probability distribution isdefined as 119864(119909

119894minus 119909)119903 where 119909 is the mean of the distribution

Also 119864(119909) shows the expected value of the variate 119909 andis defined as the first moment of the probability distributionabout 119909 = 0 that is

1205831015840

1= 119864 (119909) = int

119887

119886

119909119891 (119909) 119889119909 (20)

18 GammaDistribution A continuous random variable119885 issaid to have a gamma distribution with parameter 119898 gt 0 ifits probability distribution function is defined by

119891 (119911) =

1

Γ (119898)119911119898minus1

119890minus119911

0 ≦ 119911 lt infin

0 elsewhere(21)

and its distribution function 119865(119911) is defined by

119865 (119911) =

int

119911

0

1

Γ (119898)119911119898minus1

119890minus119911

119889119911 119911 ge 0

0 119911 lt 0

(22)

which is also called the incomplete gamma function

19 Moment Generating Function of Gamma DistributionThemoment generating function of 119885 is defined by

1198720(119905) = 119864 (119890

119905119885

) = int

infin

0

119890119905119885

119891 (119911) 119889119911

= int

infin

0

1

Γ (119898)119911119898minus1

119890minus119911(1minus119905)

119889119911

(23)

110 Beta Distribution of the First Kind A continuous ran-dom variable 119885 is said to have a beta distribution with twoparameters119898 and 119899 if its probability distribution function isdefined by

119891 (119911) =

1

119861 (119898 119899)119911119898minus1

(1 minus 119911)119899minus1

0 ≦ 119911 ≦ 1 119898 119899 gt 0

0 elsewhere(24)

Journal of Probability and Statistics 3

This distribution is known as a beta distribution of the firstkind and a beta variable of the first kind is referred to as1205731(119898 119899) Its distribution function 119865(119911) is given by

119865 (119911)

=

0 119911 lt 0

int

119911

0

1

119861 (119898 119899)119911119898minus1

(1 minus 119911)119899minus1

119889119911 0 ≦ 119911 ≦ 1 119898 119899 gt 0

0 119911 gt 1

(25)

111 Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891 (119911) =

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

0 ≦ 119911 lt infin 119898 119899 gt 0

0 otherwise(26)

and its probability distribution function is given by

119865 (119911) = int

infin

0

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

119889119911 0 ≦ 119911 lt infin 119898 119899 gt 0

(27)

2 Main Results 119896-Gamma and119896-Beta Distributions

In this section we define gamma and beta distributions interms of a new parameter 119896 gt 0 and discuss some propertiesof these distributions in terms of 119896

Definition 1 Let 119885 be a continuous random variable then itis said to have a 119896-gamma distributionwith parameters119898 gt 0

and 119896 gt 0 if its probability density function is defined by

119891119896(119911) =

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

0 ≦ 119911 lt infin 119896 gt 0

0 elsewhere(28)

and its distribution function 119865119896(119911) is defined by

119865119896(119911) =

int

119911

0

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

119889119911 119911 gt 0

0 119911 lt 0

(29)

Proposition 2 The newly defined Γ119896(119898) distribution satisfies

the following properties

(i) The 119896-gamma distribution is the probability distribu-tion that is area under the curve is unity

(ii) The mean of 119896-gamma distribution is equal to aparameter119898

(iii) The variance of 119896-gamma distribution is equal to theproduct of two parameters119898119896

Proof of (i) Using the definition of 119896-gamma distributionalong with the relation (10) we have

int

infin

0

119891119896(119911) 119889119911 =

1

Γ119896(119898)

int

infin

0

119911119898minus1

119890minus119911119896119896

119889119911 =Γ119896(119898)

Γ119896(119898)

= 1

(30)

Proof of (ii) Asmean of a distribution is the expected value ofthe variate so the mean of the 119896-gamma distribution is givenby

119911 = 119864119896(119885) =

1

Γ119896(119898)

int

infin

0

119911 sdot 119911119898minus1

119890minus119911119896119896

119889119911 (31)

Using the definition of 119896-gamma function and the relation(13) we have

119911 =1

Γ119896(119898)

int

infin

0

119911119898

119890minus119911119896119896

119889119911 =Γ119896(119898 + 119896)

Γ119896(119898)

= 119898Γ119896(119898)

Γ119896(119898)

= 119898

(32)

Proof of (iii) As variance of a distribution is equal to 119864(1199092) minus(119864(119909))

2 so the variance of 119896-gamma distribution is calculatedas

Var119896(119885) = 119864

119896(1198852

) minus (119864119896(119885))2

(33)

Now we have to find 119864119896(1198852

) which is given by

119864119896(1198852

) =1

Γ119896(119898)

int

infin

0

1199112

sdot 119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898+1

119890minus119911119896119896

119889119911

=Γ119896(119898 + 2119896)

Γ119896(119898)

=(119898 + 119896)119898Γ

119896(119898)

Γ119896(119898)

= 119898 (119898 + 119896)

(34)

Thus we obtain the variance of 119896-gamma distribution as

1205902

119896= 119898 (119898 + 119896) minus 119898

2

= 119898119896 (35)

where 1205902119896is the notation of variance present in the literature

21 119896-Beta Distribution of First Kind Let 119885 be a continuousrandom variable then it is said to have a 119896-beta distributionof the first kindwith two parameters119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

0 ≦ 119911 ≦ 1 119898 119899 119896 gt 0

0 elsewhere(36)

4 Journal of Probability and Statistics

In the above distribution the beta variable of the first kind isreferred to as 120573

1119896(119898 119899) and its distribution function 119865

119896(119911) is

given by

119865119896(119911) =

0 119911 lt 0

int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911 0 ≦ 119911 ≦ 1

119898 119899 gt 0

0 119911 gt 1

(37)

Proposition 3 The 119896-beta distribution 1205731119896(119898 119899) satisfies the

following basic properties

(i) 119896-beta distribution is the probability distribution thatis the area of 120573

1119896(119898 119899) under a curve 119891

119896(119911) is unity

(ii) The mean of this distribution is119898(119898 + 119899)(iii) The variance of 120573

1119896(119898 119899) is119898119899119896((119898+119899)

2

(119898+119899+119896))

Proof of (i) By using the above definition of 119896-beta distribu-tion we have

int

119911

0

119865119896(119911) 119889119911 = int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(38)

By the relation (11) we get

int

119911

0

119865119896(119911) 119889119911 = int

1

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 119899)

119861119896(119898 119899)

= 1

(39)

Proof of (ii) Themean of the distribution 12058310158401119896 is given by

1205831015840

1119896= 119864119896(119885) = int

119911

0

119911119865119896(119911) 119889119911

= int

119911

0

1

119896119861119896(119898 119899)

119911 sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(40)

Using the relations (12) (13) and (16) we have

1205831015840

1119896= int

1

0

1

119896119861119896(119898 119899)

119911119898119896

(1 minus 119911)119899119896minus1

119889119911 =119861119896(119898 + 119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 119896)

=119898

119898 + 119899

(41)

Proof of (iii) The variance of 1205731119896(119898 119899) is given by

1205902

119896= (Var)

119896= 119864119896(1198852

) minus (119864119896(119885))2

(42)

119864119896(1198852

) = int

1

0

1

119896119861119896(119898 119899)

119911119898119896+1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 2119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 2119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 2119896)

=119898 (119898 + 119896)

(119898 + 119899) (119898 + 119899 + 119896)

(43)

Thus substituting the values of119864119896(1198852

) and119864119896(119885) in (42) along

with some algebraic calculations we have the desired result

22 119896-Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a 119896-beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

0 ≦ 119911 lt infin 119898 119899 119896 gt 0

0 otherwise(44)

Note The 119896-beta distribution of the second kind is denotedby 1205732119896(119898 119899)

Theorem 4 The 119896-beta function of the second kind representsa probability distribution function that is

int

infin

0

119891119896(119911) 119889119911 = 1 (45)

Proof We observe that

int

infin

0

119891119896(119911) 119889119911 = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

119889119911 (46)

Let 1 + 119911 = 1119910 so that 119889119911 = minus1198891199101199102 thus by using the

relation (11) the above equation gives

=1

120573119896(119898 119899)

1

119896int

1

0

119910119899119896minus1

(1 minus 119910)119898119896minus1

119889119910 =120573119896(119898 119899)

120573119896(119898 119899)

= 1

(47)

3 Moment Generating Function of119896-Gamma Distribution

In this section we derive the moment generating functionof continuous random variable 119885 of newly defined 119896-gamma

Journal of Probability and Statistics 5

distribution in terms of a new parameter 119896 gt 0 which isillustrated as

1198720119896(119905) = 119864

119896(119890119905119885119896

) = int

infin

0

1

Γ119896(119898)

119890119905119911119896

119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898minus1

119890(minus119911119896119896)(1minus119896119905)

119889119911

(48)

Let 119906 = 119911(1minus119896119905)1119896 so that 119911 = 119906(1minus119896119905)

1119896 and 119889119911 = 119889119906(1minus

119896119905)1119896 Then substituting these values in (48) we obtain

1198720119896(119905) =

1

(1 minus 119896119905)(119898minus1)119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

(1 minus 119896119905)1119896

=1

(1 minus 119896119905)119898119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

=Γ119896(119898)

(1 minus 119896119905)119898119896

Γ119896(119898)

= (1 minus 119896119905)minus119898119896

|119896119905| lt 1

(49)

Now differentiating 119903 times 1198720119896(119905) with respect to 119905 and

putting 119905 = 0 we get

1205831015840

119903119896= 119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896) (50)

Thus when 119903 = 1 we obtain 1205831015840

1119896= 119898 when 119903 = 2 1205831015840

2119896=

119898(119898+ 119896) and hence 1205832119896

= 12058310158402

1119896minus 1205831015840

2119896= 119898119896 = variance of the

119896-gamma distribution proved in Proposition 2

31 Higher Moment in terms of 119896 The 119903th moment in termsof 119896 is given by

1205831015840

119903119896

= 119864 (119885119903

) =1

119896119861119896(119898 119899)

int

1

0

119911119903

sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=1

119896119861119896(119898 119899)

int

1

0

119911119898119896+119903minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 119903119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119898 + 119903119896 + 119899)

=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119898 + 119899) (119898 + 119899 + 119896) (119898 + 119899 + 2119896) sdot sdot sdot (119898 + 119899 + (119903 minus 1) 119896)

(51)

Theorem 5 The moments of the higher order of 119896-betadistribution of the second kind are given as

1205831015840

119903119896=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119899 minus 119896) (119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) (52)

Proof Consider

1205831015840

119903119896= 119864 (119885

119903

) = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1+119903

(1 + 119911)(119898+119899)119896

119889119911 (53)

Changing the variables as 119911 = (1 minus 119910)119910 rArr 119889119911 = (minus11199102

)119889119910above equation becomes

=1

119896120573119896(119898 119899)

int

1

0

119910119899119896minus119903minus1

(1 minus 119910)119898119896+119903minus1

119889119910 (54)

Replacing (1 minus 119910) by 119905 we have

1205831015840

119903119896=

1

120573119896(119898 119899)

1

119896int

1

0

119905119898119896+119903minus1

(1 minus 119905)119899119896minus119903minus1

119889119905

=120573119896(119898 + 119903119896 119899 minus 119903119896)

120573119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896)

Γ119896(119898) Γ119896(119899)

(55)

Now using Γ119896(119899 minus 119903119896) = Γ

119896(119899)(119899 minus 119896)(119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) in

the above equation we get the desired result

4 Conclusion

In this paper the authors conclude that we have the following

(i) If 119896 tends to 1 then 119896-gamma distribution and 119896-beta distribution tend to classical gamma and betadistribution

(ii) The authors also conclude that the area of 119896-gammadistribution and 119896-beta distribution for each positivevalue of 119896 is one and theirmean is equal to a parameter119898 and 119898(119898 + 119899) respectively The variance of 119896-gamma distribution for each positive value of 119896 isequal to 119896 times of the parameter 119898 In this case if119896 = 1 then it will be equal to variance of gammadistribution The variance of 119896-beta distribution foreach positive value of 119896 is also defined

(iii) In this paper the authors introduced moments gener-ating function and higher moments in terms of a newparameter 119896 gt 0

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to express profound gratitude toreferees for deeper review of this paper and the refereersquos usefulsuggestions that led to an improved presentation of the paper

References

[1] E D Rainville Special Functions The Macmillan New YorkNY USA 1960

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Discrete Dynamics in Nature and Society

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Decision SciencesAdvances in

Discrete MathematicsJournal of

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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 3: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

Journal of Probability and Statistics 3

This distribution is known as a beta distribution of the firstkind and a beta variable of the first kind is referred to as1205731(119898 119899) Its distribution function 119865(119911) is given by

119865 (119911)

=

0 119911 lt 0

int

119911

0

1

119861 (119898 119899)119911119898minus1

(1 minus 119911)119899minus1

119889119911 0 ≦ 119911 ≦ 1 119898 119899 gt 0

0 119911 gt 1

(25)

111 Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891 (119911) =

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

0 ≦ 119911 lt infin 119898 119899 gt 0

0 otherwise(26)

and its probability distribution function is given by

119865 (119911) = int

infin

0

1

120573 (119898 119899)

119911119898minus1

(1 + 119911)119898+119899

119889119911 0 ≦ 119911 lt infin 119898 119899 gt 0

(27)

2 Main Results 119896-Gamma and119896-Beta Distributions

In this section we define gamma and beta distributions interms of a new parameter 119896 gt 0 and discuss some propertiesof these distributions in terms of 119896

Definition 1 Let 119885 be a continuous random variable then itis said to have a 119896-gamma distributionwith parameters119898 gt 0

and 119896 gt 0 if its probability density function is defined by

119891119896(119911) =

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

0 ≦ 119911 lt infin 119896 gt 0

0 elsewhere(28)

and its distribution function 119865119896(119911) is defined by

119865119896(119911) =

int

119911

0

1

Γ119896(119898)

119911119898minus1

119890minus119911119896119896

119889119911 119911 gt 0

0 119911 lt 0

(29)

Proposition 2 The newly defined Γ119896(119898) distribution satisfies

the following properties

(i) The 119896-gamma distribution is the probability distribu-tion that is area under the curve is unity

(ii) The mean of 119896-gamma distribution is equal to aparameter119898

(iii) The variance of 119896-gamma distribution is equal to theproduct of two parameters119898119896

Proof of (i) Using the definition of 119896-gamma distributionalong with the relation (10) we have

int

infin

0

119891119896(119911) 119889119911 =

1

Γ119896(119898)

int

infin

0

119911119898minus1

119890minus119911119896119896

119889119911 =Γ119896(119898)

Γ119896(119898)

= 1

(30)

Proof of (ii) Asmean of a distribution is the expected value ofthe variate so the mean of the 119896-gamma distribution is givenby

119911 = 119864119896(119885) =

1

Γ119896(119898)

int

infin

0

119911 sdot 119911119898minus1

119890minus119911119896119896

119889119911 (31)

Using the definition of 119896-gamma function and the relation(13) we have

119911 =1

Γ119896(119898)

int

infin

0

119911119898

119890minus119911119896119896

119889119911 =Γ119896(119898 + 119896)

Γ119896(119898)

= 119898Γ119896(119898)

Γ119896(119898)

= 119898

(32)

Proof of (iii) As variance of a distribution is equal to 119864(1199092) minus(119864(119909))

2 so the variance of 119896-gamma distribution is calculatedas

Var119896(119885) = 119864

119896(1198852

) minus (119864119896(119885))2

(33)

Now we have to find 119864119896(1198852

) which is given by

119864119896(1198852

) =1

Γ119896(119898)

int

infin

0

1199112

sdot 119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898+1

119890minus119911119896119896

119889119911

=Γ119896(119898 + 2119896)

Γ119896(119898)

=(119898 + 119896)119898Γ

119896(119898)

Γ119896(119898)

= 119898 (119898 + 119896)

(34)

Thus we obtain the variance of 119896-gamma distribution as

1205902

119896= 119898 (119898 + 119896) minus 119898

2

= 119898119896 (35)

where 1205902119896is the notation of variance present in the literature

21 119896-Beta Distribution of First Kind Let 119885 be a continuousrandom variable then it is said to have a 119896-beta distributionof the first kindwith two parameters119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

0 ≦ 119911 ≦ 1 119898 119899 119896 gt 0

0 elsewhere(36)

4 Journal of Probability and Statistics

In the above distribution the beta variable of the first kind isreferred to as 120573

1119896(119898 119899) and its distribution function 119865

119896(119911) is

given by

119865119896(119911) =

0 119911 lt 0

int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911 0 ≦ 119911 ≦ 1

119898 119899 gt 0

0 119911 gt 1

(37)

Proposition 3 The 119896-beta distribution 1205731119896(119898 119899) satisfies the

following basic properties

(i) 119896-beta distribution is the probability distribution thatis the area of 120573

1119896(119898 119899) under a curve 119891

119896(119911) is unity

(ii) The mean of this distribution is119898(119898 + 119899)(iii) The variance of 120573

1119896(119898 119899) is119898119899119896((119898+119899)

2

(119898+119899+119896))

Proof of (i) By using the above definition of 119896-beta distribu-tion we have

int

119911

0

119865119896(119911) 119889119911 = int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(38)

By the relation (11) we get

int

119911

0

119865119896(119911) 119889119911 = int

1

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 119899)

119861119896(119898 119899)

= 1

(39)

Proof of (ii) Themean of the distribution 12058310158401119896 is given by

1205831015840

1119896= 119864119896(119885) = int

119911

0

119911119865119896(119911) 119889119911

= int

119911

0

1

119896119861119896(119898 119899)

119911 sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(40)

Using the relations (12) (13) and (16) we have

1205831015840

1119896= int

1

0

1

119896119861119896(119898 119899)

119911119898119896

(1 minus 119911)119899119896minus1

119889119911 =119861119896(119898 + 119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 119896)

=119898

119898 + 119899

(41)

Proof of (iii) The variance of 1205731119896(119898 119899) is given by

1205902

119896= (Var)

119896= 119864119896(1198852

) minus (119864119896(119885))2

(42)

119864119896(1198852

) = int

1

0

1

119896119861119896(119898 119899)

119911119898119896+1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 2119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 2119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 2119896)

=119898 (119898 + 119896)

(119898 + 119899) (119898 + 119899 + 119896)

(43)

Thus substituting the values of119864119896(1198852

) and119864119896(119885) in (42) along

with some algebraic calculations we have the desired result

22 119896-Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a 119896-beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

0 ≦ 119911 lt infin 119898 119899 119896 gt 0

0 otherwise(44)

Note The 119896-beta distribution of the second kind is denotedby 1205732119896(119898 119899)

Theorem 4 The 119896-beta function of the second kind representsa probability distribution function that is

int

infin

0

119891119896(119911) 119889119911 = 1 (45)

Proof We observe that

int

infin

0

119891119896(119911) 119889119911 = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

119889119911 (46)

Let 1 + 119911 = 1119910 so that 119889119911 = minus1198891199101199102 thus by using the

relation (11) the above equation gives

=1

120573119896(119898 119899)

1

119896int

1

0

119910119899119896minus1

(1 minus 119910)119898119896minus1

119889119910 =120573119896(119898 119899)

120573119896(119898 119899)

= 1

(47)

3 Moment Generating Function of119896-Gamma Distribution

In this section we derive the moment generating functionof continuous random variable 119885 of newly defined 119896-gamma

Journal of Probability and Statistics 5

distribution in terms of a new parameter 119896 gt 0 which isillustrated as

1198720119896(119905) = 119864

119896(119890119905119885119896

) = int

infin

0

1

Γ119896(119898)

119890119905119911119896

119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898minus1

119890(minus119911119896119896)(1minus119896119905)

119889119911

(48)

Let 119906 = 119911(1minus119896119905)1119896 so that 119911 = 119906(1minus119896119905)

1119896 and 119889119911 = 119889119906(1minus

119896119905)1119896 Then substituting these values in (48) we obtain

1198720119896(119905) =

1

(1 minus 119896119905)(119898minus1)119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

(1 minus 119896119905)1119896

=1

(1 minus 119896119905)119898119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

=Γ119896(119898)

(1 minus 119896119905)119898119896

Γ119896(119898)

= (1 minus 119896119905)minus119898119896

|119896119905| lt 1

(49)

Now differentiating 119903 times 1198720119896(119905) with respect to 119905 and

putting 119905 = 0 we get

1205831015840

119903119896= 119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896) (50)

Thus when 119903 = 1 we obtain 1205831015840

1119896= 119898 when 119903 = 2 1205831015840

2119896=

119898(119898+ 119896) and hence 1205832119896

= 12058310158402

1119896minus 1205831015840

2119896= 119898119896 = variance of the

119896-gamma distribution proved in Proposition 2

31 Higher Moment in terms of 119896 The 119903th moment in termsof 119896 is given by

1205831015840

119903119896

= 119864 (119885119903

) =1

119896119861119896(119898 119899)

int

1

0

119911119903

sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=1

119896119861119896(119898 119899)

int

1

0

119911119898119896+119903minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 119903119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119898 + 119903119896 + 119899)

=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119898 + 119899) (119898 + 119899 + 119896) (119898 + 119899 + 2119896) sdot sdot sdot (119898 + 119899 + (119903 minus 1) 119896)

(51)

Theorem 5 The moments of the higher order of 119896-betadistribution of the second kind are given as

1205831015840

119903119896=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119899 minus 119896) (119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) (52)

Proof Consider

1205831015840

119903119896= 119864 (119885

119903

) = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1+119903

(1 + 119911)(119898+119899)119896

119889119911 (53)

Changing the variables as 119911 = (1 minus 119910)119910 rArr 119889119911 = (minus11199102

)119889119910above equation becomes

=1

119896120573119896(119898 119899)

int

1

0

119910119899119896minus119903minus1

(1 minus 119910)119898119896+119903minus1

119889119910 (54)

Replacing (1 minus 119910) by 119905 we have

1205831015840

119903119896=

1

120573119896(119898 119899)

1

119896int

1

0

119905119898119896+119903minus1

(1 minus 119905)119899119896minus119903minus1

119889119905

=120573119896(119898 + 119903119896 119899 minus 119903119896)

120573119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896)

Γ119896(119898) Γ119896(119899)

(55)

Now using Γ119896(119899 minus 119903119896) = Γ

119896(119899)(119899 minus 119896)(119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) in

the above equation we get the desired result

4 Conclusion

In this paper the authors conclude that we have the following

(i) If 119896 tends to 1 then 119896-gamma distribution and 119896-beta distribution tend to classical gamma and betadistribution

(ii) The authors also conclude that the area of 119896-gammadistribution and 119896-beta distribution for each positivevalue of 119896 is one and theirmean is equal to a parameter119898 and 119898(119898 + 119899) respectively The variance of 119896-gamma distribution for each positive value of 119896 isequal to 119896 times of the parameter 119898 In this case if119896 = 1 then it will be equal to variance of gammadistribution The variance of 119896-beta distribution foreach positive value of 119896 is also defined

(iii) In this paper the authors introduced moments gener-ating function and higher moments in terms of a newparameter 119896 gt 0

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to express profound gratitude toreferees for deeper review of this paper and the refereersquos usefulsuggestions that led to an improved presentation of the paper

References

[1] E D Rainville Special Functions The Macmillan New YorkNY USA 1960

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 4: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

4 Journal of Probability and Statistics

In the above distribution the beta variable of the first kind isreferred to as 120573

1119896(119898 119899) and its distribution function 119865

119896(119911) is

given by

119865119896(119911) =

0 119911 lt 0

int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911 0 ≦ 119911 ≦ 1

119898 119899 gt 0

0 119911 gt 1

(37)

Proposition 3 The 119896-beta distribution 1205731119896(119898 119899) satisfies the

following basic properties

(i) 119896-beta distribution is the probability distribution thatis the area of 120573

1119896(119898 119899) under a curve 119891

119896(119911) is unity

(ii) The mean of this distribution is119898(119898 + 119899)(iii) The variance of 120573

1119896(119898 119899) is119898119899119896((119898+119899)

2

(119898+119899+119896))

Proof of (i) By using the above definition of 119896-beta distribu-tion we have

int

119911

0

119865119896(119911) 119889119911 = int

119911

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(38)

By the relation (11) we get

int

119911

0

119865119896(119911) 119889119911 = int

1

0

1

119896119861119896(119898 119899)

119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 119899)

119861119896(119898 119899)

= 1

(39)

Proof of (ii) Themean of the distribution 12058310158401119896 is given by

1205831015840

1119896= 119864119896(119885) = int

119911

0

119911119865119896(119911) 119889119911

= int

119911

0

1

119896119861119896(119898 119899)

119911 sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

0 ≦ 119911 ≦ 1 119898 119899 gt 0

(40)

Using the relations (12) (13) and (16) we have

1205831015840

1119896= int

1

0

1

119896119861119896(119898 119899)

119911119898119896

(1 minus 119911)119899119896minus1

119889119911 =119861119896(119898 + 119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 119896)

=119898

119898 + 119899

(41)

Proof of (iii) The variance of 1205731119896(119898 119899) is given by

1205902

119896= (Var)

119896= 119864119896(1198852

) minus (119864119896(119885))2

(42)

119864119896(1198852

) = int

1

0

1

119896119861119896(119898 119899)

119911119898119896+1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 2119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 2119896) Γ

119896(119899) Γ119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899 + 2119896)

=119898 (119898 + 119896)

(119898 + 119899) (119898 + 119899 + 119896)

(43)

Thus substituting the values of119864119896(1198852

) and119864119896(119885) in (42) along

with some algebraic calculations we have the desired result

22 119896-Beta Distribution of the Second Kind A continuousrandom variable 119885 is said to have a 119896-beta distribution ofthe second kind with parameters 119898 and 119899 if its probabilitydistribution function is defined by

119891119896(119911)

=

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

0 ≦ 119911 lt infin 119898 119899 119896 gt 0

0 otherwise(44)

Note The 119896-beta distribution of the second kind is denotedby 1205732119896(119898 119899)

Theorem 4 The 119896-beta function of the second kind representsa probability distribution function that is

int

infin

0

119891119896(119911) 119889119911 = 1 (45)

Proof We observe that

int

infin

0

119891119896(119911) 119889119911 = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1

(1 + 119911)(119898+119899)119896

119889119911 (46)

Let 1 + 119911 = 1119910 so that 119889119911 = minus1198891199101199102 thus by using the

relation (11) the above equation gives

=1

120573119896(119898 119899)

1

119896int

1

0

119910119899119896minus1

(1 minus 119910)119898119896minus1

119889119910 =120573119896(119898 119899)

120573119896(119898 119899)

= 1

(47)

3 Moment Generating Function of119896-Gamma Distribution

In this section we derive the moment generating functionof continuous random variable 119885 of newly defined 119896-gamma

Journal of Probability and Statistics 5

distribution in terms of a new parameter 119896 gt 0 which isillustrated as

1198720119896(119905) = 119864

119896(119890119905119885119896

) = int

infin

0

1

Γ119896(119898)

119890119905119911119896

119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898minus1

119890(minus119911119896119896)(1minus119896119905)

119889119911

(48)

Let 119906 = 119911(1minus119896119905)1119896 so that 119911 = 119906(1minus119896119905)

1119896 and 119889119911 = 119889119906(1minus

119896119905)1119896 Then substituting these values in (48) we obtain

1198720119896(119905) =

1

(1 minus 119896119905)(119898minus1)119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

(1 minus 119896119905)1119896

=1

(1 minus 119896119905)119898119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

=Γ119896(119898)

(1 minus 119896119905)119898119896

Γ119896(119898)

= (1 minus 119896119905)minus119898119896

|119896119905| lt 1

(49)

Now differentiating 119903 times 1198720119896(119905) with respect to 119905 and

putting 119905 = 0 we get

1205831015840

119903119896= 119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896) (50)

Thus when 119903 = 1 we obtain 1205831015840

1119896= 119898 when 119903 = 2 1205831015840

2119896=

119898(119898+ 119896) and hence 1205832119896

= 12058310158402

1119896minus 1205831015840

2119896= 119898119896 = variance of the

119896-gamma distribution proved in Proposition 2

31 Higher Moment in terms of 119896 The 119903th moment in termsof 119896 is given by

1205831015840

119903119896

= 119864 (119885119903

) =1

119896119861119896(119898 119899)

int

1

0

119911119903

sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=1

119896119861119896(119898 119899)

int

1

0

119911119898119896+119903minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 119903119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119898 + 119903119896 + 119899)

=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119898 + 119899) (119898 + 119899 + 119896) (119898 + 119899 + 2119896) sdot sdot sdot (119898 + 119899 + (119903 minus 1) 119896)

(51)

Theorem 5 The moments of the higher order of 119896-betadistribution of the second kind are given as

1205831015840

119903119896=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119899 minus 119896) (119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) (52)

Proof Consider

1205831015840

119903119896= 119864 (119885

119903

) = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1+119903

(1 + 119911)(119898+119899)119896

119889119911 (53)

Changing the variables as 119911 = (1 minus 119910)119910 rArr 119889119911 = (minus11199102

)119889119910above equation becomes

=1

119896120573119896(119898 119899)

int

1

0

119910119899119896minus119903minus1

(1 minus 119910)119898119896+119903minus1

119889119910 (54)

Replacing (1 minus 119910) by 119905 we have

1205831015840

119903119896=

1

120573119896(119898 119899)

1

119896int

1

0

119905119898119896+119903minus1

(1 minus 119905)119899119896minus119903minus1

119889119905

=120573119896(119898 + 119903119896 119899 minus 119903119896)

120573119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896)

Γ119896(119898) Γ119896(119899)

(55)

Now using Γ119896(119899 minus 119903119896) = Γ

119896(119899)(119899 minus 119896)(119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) in

the above equation we get the desired result

4 Conclusion

In this paper the authors conclude that we have the following

(i) If 119896 tends to 1 then 119896-gamma distribution and 119896-beta distribution tend to classical gamma and betadistribution

(ii) The authors also conclude that the area of 119896-gammadistribution and 119896-beta distribution for each positivevalue of 119896 is one and theirmean is equal to a parameter119898 and 119898(119898 + 119899) respectively The variance of 119896-gamma distribution for each positive value of 119896 isequal to 119896 times of the parameter 119898 In this case if119896 = 1 then it will be equal to variance of gammadistribution The variance of 119896-beta distribution foreach positive value of 119896 is also defined

(iii) In this paper the authors introduced moments gener-ating function and higher moments in terms of a newparameter 119896 gt 0

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to express profound gratitude toreferees for deeper review of this paper and the refereersquos usefulsuggestions that led to an improved presentation of the paper

References

[1] E D Rainville Special Functions The Macmillan New YorkNY USA 1960

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 5: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

Journal of Probability and Statistics 5

distribution in terms of a new parameter 119896 gt 0 which isillustrated as

1198720119896(119905) = 119864

119896(119890119905119885119896

) = int

infin

0

1

Γ119896(119898)

119890119905119911119896

119911119898minus1

119890minus119911119896119896

119889119911

=1

Γ119896(119898)

int

infin

0

119911119898minus1

119890(minus119911119896119896)(1minus119896119905)

119889119911

(48)

Let 119906 = 119911(1minus119896119905)1119896 so that 119911 = 119906(1minus119896119905)

1119896 and 119889119911 = 119889119906(1minus

119896119905)1119896 Then substituting these values in (48) we obtain

1198720119896(119905) =

1

(1 minus 119896119905)(119898minus1)119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

(1 minus 119896119905)1119896

=1

(1 minus 119896119905)119898119896

Γ119896(119898)

int

infin

0

119906119898minus1

119890minus119906119896119896

119889119906

=Γ119896(119898)

(1 minus 119896119905)119898119896

Γ119896(119898)

= (1 minus 119896119905)minus119898119896

|119896119905| lt 1

(49)

Now differentiating 119903 times 1198720119896(119905) with respect to 119905 and

putting 119905 = 0 we get

1205831015840

119903119896= 119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896) (50)

Thus when 119903 = 1 we obtain 1205831015840

1119896= 119898 when 119903 = 2 1205831015840

2119896=

119898(119898+ 119896) and hence 1205832119896

= 12058310158402

1119896minus 1205831015840

2119896= 119898119896 = variance of the

119896-gamma distribution proved in Proposition 2

31 Higher Moment in terms of 119896 The 119903th moment in termsof 119896 is given by

1205831015840

119903119896

= 119864 (119885119903

) =1

119896119861119896(119898 119899)

int

1

0

119911119903

sdot 119911119898119896minus1

(1 minus 119911)119899119896minus1

119889119911

=1

119896119861119896(119898 119899)

int

1

0

119911119898119896+119903minus1

(1 minus 119911)119899119896minus1

119889119911

=119861119896(119898 + 119903119896 119899)

119861119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119898 + 119903119896 + 119899)

=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119898 + 119899) (119898 + 119899 + 119896) (119898 + 119899 + 2119896) sdot sdot sdot (119898 + 119899 + (119903 minus 1) 119896)

(51)

Theorem 5 The moments of the higher order of 119896-betadistribution of the second kind are given as

1205831015840

119903119896=119898 (119898 + 119896) (119898 + 2119896) sdot sdot sdot (119898 + (119903 minus 1) 119896)

(119899 minus 119896) (119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) (52)

Proof Consider

1205831015840

119903119896= 119864 (119885

119903

) = int

infin

0

1

119896120573119896(119898 119899)

119911119898119896minus1+119903

(1 + 119911)(119898+119899)119896

119889119911 (53)

Changing the variables as 119911 = (1 minus 119910)119910 rArr 119889119911 = (minus11199102

)119889119910above equation becomes

=1

119896120573119896(119898 119899)

int

1

0

119910119899119896minus119903minus1

(1 minus 119910)119898119896+119903minus1

119889119910 (54)

Replacing (1 minus 119910) by 119905 we have

1205831015840

119903119896=

1

120573119896(119898 119899)

1

119896int

1

0

119905119898119896+119903minus1

(1 minus 119905)119899119896minus119903minus1

119889119905

=120573119896(119898 + 119903119896 119899 minus 119903119896)

120573119896(119898 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896) Γ

119896(119898 + 119899)

Γ119896(119898) Γ119896(119899) Γ119896(119898 + 119899)

=Γ119896(119898 + 119903119896) Γ

119896(119899 minus 119903119896)

Γ119896(119898) Γ119896(119899)

(55)

Now using Γ119896(119899 minus 119903119896) = Γ

119896(119899)(119899 minus 119896)(119899 minus 2119896) sdot sdot sdot (119899 minus 119903119896) in

the above equation we get the desired result

4 Conclusion

In this paper the authors conclude that we have the following

(i) If 119896 tends to 1 then 119896-gamma distribution and 119896-beta distribution tend to classical gamma and betadistribution

(ii) The authors also conclude that the area of 119896-gammadistribution and 119896-beta distribution for each positivevalue of 119896 is one and theirmean is equal to a parameter119898 and 119898(119898 + 119899) respectively The variance of 119896-gamma distribution for each positive value of 119896 isequal to 119896 times of the parameter 119898 In this case if119896 = 1 then it will be equal to variance of gammadistribution The variance of 119896-beta distribution foreach positive value of 119896 is also defined

(iii) In this paper the authors introduced moments gener-ating function and higher moments in terms of a newparameter 119896 gt 0

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to express profound gratitude toreferees for deeper review of this paper and the refereersquos usefulsuggestions that led to an improved presentation of the paper

References

[1] E D Rainville Special Functions The Macmillan New YorkNY USA 1960

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 6: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

6 Journal of Probability and Statistics

[2] R Diaz and E Pariguan ldquoOn hypergeometric functions andPochhammer 119896-symbolrdquoDivulgacionesMatematicas vol 15 no2 pp 179ndash192 2007

[3] M G Kendall and A StuartThe Advanced Theory of Statisticsvol 2 Charles Griffin and Company London UK 1961

[4] R J Larsen and M L Marx An Introduction to MathematicalStatistics and Its Applications Prentice-Hall International 5thedition 2011

[5] C Walac A Hand Book on Statictical Distributations for Exper-imentalist 2007

[6] C G Kokologiannaki ldquoProperties and inequalities of general-ized 119896-gamma beta and zeta functionsrdquo International Journal ofContemporary Mathematical Sciences vol 5 no 13ndash16 pp 653ndash660 2010

[7] C G Kokologiannaki and V Krasniqi ldquoSome properties of the119896-gamma functionrdquo Le Matematiche vol 68 no 1 pp 13ndash222013

[8] V Krasniqi ldquoA limit for the $k$-gamma and $k$-beta functionrdquoInternational Mathematical Forum vol 5 no 33 pp 1613ndash16172010

[9] M Mansoor ldquoDetermining the k-generalized gamma functionΓ119870X by functional equationsrdquo Journal of Contemporary Mathe-

matical Sciences vol 4 no 2 pp 1037ndash1042 2009[10] S Mubeen andGM Habibullah ldquoAn integral representation of

some 119896-hypergeometric functionsrdquo International MathematicalForum vol 7 no 1ndash4 pp 203ndash207 2012

[11] S Mubeen and G M Habibullah ldquo119896-fractional integrals andapplicationrdquo International Journal of Contemporary Mathemat-ical Sciences vol 7 no 1ndash4 pp 89ndash94 2012

[12] S Mubeen M Naz and G Rahman ldquoA note on 119896-hyper-gemetric differential equationsrdquo Journal of Inequalities andSpecial Functions vol 4 no 3 pp 38ndash43 2013

[13] S Mubeen G Rahman A Rehman and M Naz ldquoContiguousfunction relations for 119896-hypergeometric functionsrdquo ISRNMath-ematical Analysis vol 2014 Article ID 410801 6 pages 2014

[14] S Mubeen M Naz A Rehman and G Rahman ldquoSolutionsof 119896-hypergeometric differential equationsrdquo Journal of AppliedMathematics vol 2014 Article ID 128787 13 pages 2014

[15] F Merovci ldquoPower product inequalities for the Γ119896functionrdquo

International Journal ofMathematical Analysis vol 4 no 21 pp1007ndash1012 2010

[16] S Mubeen A Rehman and F Shaheen ldquoProperties of 119896-gamma 119896-beta and 119896-psi functionsrdquo Bothalia Journal vol 4 pp371ndash379 2014

[17] A Rehman S Mubeen N Sadiq and F Shaheen ldquoSomeinequalities involving k-gamma and k-beta functions withapplicationsrdquo Journal of Inequalities and Applications vol 2014article 224 16 pages 2014

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 7: Research Article -Gamma and -Beta Distributions and Moment … · 2019. 7. 31. · In statistics, there are three types of moments which are (i) moments about any point = , (ii) moments

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of


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