I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
1
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
OUTLINE
Analysis of Data and Model
Hypothesis Testing
Dummy Variables
Research in Finance
2
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Trend
Seasonal Variation
Cyclical Variation
Irregular Variation
Time Series data Cross-Sectional data
1-dimensional Data set
Observing many subjects
(size, company, counties,
etc) at the same time
Panel data
Multi-dimensional data set
Time-Series + Cross-
Sectional Data
MULTIPLE REGRESSION
ANALYSIS: Types of Data
3
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Trend Component• Persistent, overall upward or downward pattern
• Due to population, technology etc.
• Several years duration
Mo., Qtr., Yr.
Response
© 1984-1994 T/Maker Co.
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Trend Component• Overall Upward or Downward Movement
• Data Taken Over a Period of Years
Sales
Time
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Cyclical Component
• Repeating up & down movements
• Due to interactions of factors influencing economy
• Usually 2-10 years duration
Mo., Qtr., Yr.
Response
Cycle
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Cyclical Component
• Upward or Downward Swings
• May Vary in Length
• Usually Lasts 2 - 10 Years
Sales
Time
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Seasonal Component
• Regular pattern of up & down fluctuations
• Due to weather, customs etc.
• Occurs within one year
Mo., Qtr.
Response
Summer
© 1984-1994 T/Maker Co.
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Seasonal Component
• Upward or Downward Swings
• Regular Patterns
• Observed Within One Year
Sales
Time (Monthly or Quarterly)
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Irregular Component
• Erratic, unsystematic, ‘residual’
fluctuations
• Due to random variation or unforeseen
events
– Union strike
– War
• Short duration & nonrepeating
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Time Series Data
0
200
400
600
800
1000
1200
1400
1600
1800
2000
Ap
r-7
5
May
-76
Jun
-77
Jul-
78
Au
g-7
9
Sep
-80
Oct
-81
No
v-8
2
Dec
-83
Jan
-85
Feb
-86
Mar
-87
Ap
r-8
8
May
-89
Jun
-90
Jul-
91
Au
g-9
2
Sep
-93
Oct
-94
No
v-9
5
Dec
-96
Jan
-98
Feb
-99
Mar
-00
Ap
r-0
1
May
-02
Jun
-03
Jul-
04
Au
g-0
5
Sep
-06
Oct
-07
No
v-0
8
Dec
-09
Jan
-11
Feb
-12
Mar
-13
Ap
r-1
4
May
-15
Jun
-16
Jul-
17
SET Index
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Cross Sectional Data
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Pool (Panel) Data
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Least Square Estimator Maximum Likelihood Estimator
𝑌𝑖 = 𝛽1 + 𝛽2𝑋1𝑖 + 𝛽3𝑋2𝑖 + 𝑢𝑖
ANALYSIS: Type of Estimator
14
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Linear model Non Linear Model
𝑌𝑡 = 𝐴𝐼𝑆 𝑅𝐸𝑇𝑈𝑅𝑁𝐷𝑇𝐴𝐶𝑡 = 𝛼 + 𝛽1𝑋1𝑡 + 𝛽2 𝑋2𝑡 + 𝜀𝑡
ANALYSIS: Type of Model
15
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Y = a + b x
Time series Panel Model
Pooled or Panel Model
Fixed-Effect Model
Random-Effect Model
Time-Series with Condition
ARCH/GARCH Multiple Regression ARMA/ ARIMA
X ~ regressor
independent variable
explanatory variable
predictor Variable
Y ~ regressand var
response var
dependent var
observed var
ANALYSIS: Fitted Regression on Model
16
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Y = a + b x
Logit Model Probit ModelY is discrete
ANALYSIS: Fitted Regression on Model
17
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Y = a + b x
Vector Auto Regression
(VAR)
Error Correction
Model (ECM)
Y and X are Dynamic
ANALYSIS: Fitted Regression on Model
18
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
FITTED REGRESSION MODEL
Y = a + b x
ANALYSIS: Expansion from Simple Regression to Multiple Regression
19
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
simple linear regression
• x is the independent variable
• y is the dependent variable
• The regression model is
• The model has two variables, the independent or explanatory
variable, x, and the dependent variable y, the variable whose
variation is to be explained.
• The relationship between x and y is a linear or straight line
relationship.
• Two parameters to estimate – the slope of the line β1 and the y-
intercept β0 (where the line crosses the vertical axis).
• ε is the unexplained, random, or error component. Much more on
this later.
xy 10
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Regression line
• The regression model is
• Data about x and y are obtained from a sample.
• From the sample of values of x and y, estimates b0 of β0
and b1 of β1 are obtained using the least squares or
another method.
• The resulting estimate of the model is
• The symbol is termed “y hat” and refers to the
predicted values of the dependent variable y that are
associated with values of x, given the linear model.
xy 10
xbby 10ˆ
y
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Income hrs/week Income hrs/week
8000 38 8000 35
6400 50 18000 37.5
2500 15 5400 37
3000 30 15000 35
6000 50 3500 30
5000 38 24000 45
8000 50 1000 4
4000 20 8000 37.5
11000 45 2100 25
25000 50 8000 46
4000 20 4000 30
8800 35 1000 200
5000 30 2000 200
7000 43 4800 30
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Summer Income as a Function of Hours Worked
0
5000
10000
15000
20000
25000
30000
0 10 20 30 40 50 60
Hours per Week
Inc
om
e
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
xy 2972461ˆ R2 = 0.311
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Outliers
• Rare, extreme values may distort the outcome.
– Could be an error.
– Could be a very important observation.
• Outlier: more than 3 standard deviations from the
mean.
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
GPA vs. Time Online
0
2
4
6
8
10
12
50 55 60 65 70 75 80 85 90 95 100
GPA
Tim
e O
nlin
e
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
GPA vs. Time Online
0
1
2
3
4
5
6
7
8
9
50 55 60 65 70 75 80 85 90 95 100
GPA
Tim
e O
nlin
e
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
U-Shaped Relationship
0
2
4
6
8
10
12
0 2 4 6 8 10 12
X
Y
Correlation = +0.12.
OMITTED VARIABLE
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• F-Test is of interest to test more than one
coefficient simultaneously.
F-Test
Conditional to Reject H0:
Significant if p-value < 0.05
TESTING MULTIPLE HYPOTHESIS: F-test
31
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• t-Test is of interest to test ONLY one coefficient
t-Test
Conditional to Reject H0:
Significant if p-value < 0.05
Oh my gosh!!!! It fails to reject H0, what does it mean?
What I should do? Cut it or leave it?
TESTING MULTIPLE HYPOTHESIS: t-test
32
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
TMB
RP1BBLNPLFRNJASDJ
NIKKEI
1990M01 2011 M12
Example I: Stock Asset Price Regression
33
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Dependent Variable : Y ~ Rental Values DefinitionsExample II: Hedonic Pricing Model
34
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• R2 is desirable to answer how well regression model
actually fits the data
• In other words, R2 is desirable to answer how well does
the model containing the explanatory variables
R2 = 1 0 < R2 < 1
0 ≤ R2 ≤ 1
TESTING MULTIPLE HYPOTHESIS: Goodness of Fit Testing R2
35
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• Cannot compare R2 of two models with same X but change Y
• R2 never falls if more regressors are added to the regression
• R2 can take values of 0.9 or higher for time series regressions,
and hence it is not good at discrimanating between models
R22 R1
2
TESTING MULTIPLE HYPOTHESIS: Problem with using R2
36
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• If an extra regressor is added to the model, k increases
and unless R2 increases by a more than off-setting
amount, will actually fall.
• If model contains a lot of significant and insignificant
variables, can be negative
TESTING MULTIPLE HYPOTHESIS: Adjusted R2
37
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Dummy is variables that assume such 0 and 1 values
If a model contains M categories, then only M-1 dummy
variables should be created. Otherwise, multicollinearity
Problem
Category for which no dummy variable is assigned is
known as base, benchmark
2 types of dummy variables: Intercept vs. slope change
dummy
DUMMY VARIABLE: How to Create Dummy
38
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
Slop = Β3 + β4D
I. Different Intercept
JAN is dummy = 1 if January
= 0 otherwise
II. Different Slope
𝑅𝑡 − 𝑅𝑓= 𝛼 + 𝛽1 𝑅𝑀 − 𝑅𝑓 + 𝛽2𝑆𝑀𝐵
+ 𝛽3𝐻𝑀𝐿 + 𝛽4𝐽𝐴𝑁
X
Y
α
β4Regression for Other months
Regression for JAN
𝑅𝐸𝑁𝑇𝑡= 𝛼 + 𝛽1𝐿𝑁𝐴𝐺𝐸 + 𝛽2𝑁𝑂𝑅𝑂𝑂𝑀+ 𝛽3𝐷𝐼𝑆𝑇 + 𝛽4𝐷𝐷𝐼𝑆𝑇
D is dummy = 1 if Safe Area
= 0 Otherwise
DISTANT
RENT
Regression for Criminal Area
Regression for Safe Area
α
DUMMY VARIABLE: 2 Type of Dummy Variables
39
α+β4
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
STEP BY STEP
Quantitative Analysis (Multiple Regression)
1. Conceptual Framework
2. Choose Type of regression (Linear vs. Non Linear)
3. Group Variables
4. Analyze Data (Take logarithm or not)
5. Look at the sign of estimated parameters.
6. Test Hypothesis
7. Take a look at Adjust R2
40
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
• Three Factor Model (Fama and French (1992))
Kenneth R. FrenchEugene Fama
RESEARCH PAPER: THREE FACTOR MODEL
41
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
42
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
43
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
44
WORK SHOP
#1
I. Analysis of Data
KULKUNYA PRAYARACH, PH.D.
Multiple Regression Analysis
II. Hypothesis Testing III. Dummy Variable IV. Research & Group Work
WORK ORDERS : Multiple Regression
(1) Using Three Factor Model to regress Multiple Regression on your group assignment
(2) Interpret F-test, and T-Test.(3) Explain Adjusted R2
(4) Create Dummy variables o Monthly Data : (1) Window Dressing in June and (2)
End-Year Effect. o Annual Data : (1) Asian Crisis during 1997-1999,
(2) Subprime Crisis during 2008-2010, (3) Europe Debt crisis during 2008-2012.
(5) Redo Work Orders (1) – (4) with new model
45