GSM Operator Selection for a Call Center Investment by Using AHP
Ozcan Cavusoglu, Mustafa Canolca, Demet Bayraktar,[email protected], [email protected]; [email protected] Technical University, Faculty of Management, Department of Management
EngineeringMaçka, 34367, Istanbul, Turkey
In today’s worldwide competitive business environment, effective investment planning and partner selection is one of the key issues for companies which are planning investment in abroad. The purpose of study is to propose a selection system, will provide a comprehensive approach for selecting the best GSM operator for Call Center, is selling GSM operator’s prepaid minutes, investment. For this purpose, a literature review is performed about GSM. Then, extensive interviews have been carried out with authorized experts, and qualitative and quantitative decision factors have been defined for alternative regions, countries and GSM operators, which have been evaluated by using AHP respectively. Finally, by using developed evaluation formula, each alternative has been evaluated and, the best alternative GSM operator has been selected by using Goal Programming to investment, raw material cost, labor cost, profit and market share goals. In the conclusion of our study, the results have been discussed in detail and the future work is presented as well.
Key words: GSM, Call Center, AHP, Investment Planning, GP.
1. Introduction
In recent years, increasing importance of information and communication technologies dramatically, have been changed companies competition’ strategies and road maps, so main structure and type of investments, which are realized all over the world, have been changed [1]. Especially, due to effective network structure, low transaction cost, market growth rate and information diffusion rate, investment in telecommunication sector, have been increasing in recent years [2]. Because of that, in today’s worldwide competitive business environment, effective investment planning and partner selection become crucial issues for companies which are planning investment to GSM companies in abroad.
The aim of this study is to propose a selection system, which will provide a well-defined, and a comprehensive approach for selecting the best GSM Operator for Call Center, which is selling selected GSM operator’s prepaid minutes, investment in abroad. For this purpose, in the next section, a detailed literature review is performed in the context of investment planning about GSM and telecommunication sector. Then, extensive interviews have been carried out with authorized experts whom are working at the GSM and the Call Center companies, where the application is performed. Accordingly, qualitative and quantitative decision factors have been defined in this phase for alternative regions, countries and GSM operators. In the third section, in the first step, alternative regions have been evaluated by using AHP. In the second step, secondary data which are representing alternative countries’ characteristic have been evaluated by using AHP. In the third step, secondary data which are representing alternative GSM operators’ characteristic have been evaluated by using AHP. In the final step of this section, by using developed evaluation formula, all candidates’ GSM
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operators have been scored, ranked and the best alternative has been selected. Finally, in the last chapter, the results and the future work are argued.
2. Literature Review
In literature, many tools using for investment planning, analysis and partner selection such as Analytic Hierarchy Process (AHP), Analytic Network Process (ANP), Fuzzy AHP, Linear Programming, Goal Programming, etc. Multi objective decision support system tools are generally used to evaluate investment alternatives. In this research we evaluate some article about investment planning, analysis and partner selection then criticize what this tools are, why this tools was used to evaluate investment alternatives, who(s) is used to this tools. Summary of articles presented in Table 1.
Table 1: Methods and Tools Using in Investment Project Evaluation
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Subject / PurposeTools /
MethodologyReference
To determine production location selectionAnalytic
Network Process (ANP)
[3]
To determine production technologyAnalytic
Hierarchy Process (AHP)
[4] Created AHP model for foreign direct investment [5] IT and Communication Investment alternatives modeling by using AHP A decision support model for investment decision in new ventures
[6][7]
Concentrated breakeven point to evaluate financial investment alternatives
Breakeven Point Analysis
[8]
Decision support system for facility selection Project selection
Fuzzy AHP[9][10]
Applying concepts of fuzzy cognitive mapping to model in the IT/IS investment evaluation process
Fuzzy Cognitive Mapping
[11]
Evaluation of an investment’s finalization and closing conditions An approach in multivariable situation for decision to firms.
Dynamic Programming
[12][13]
Investment decision in under uncertainty and risk Decision support system in energy production
Sensitivity Analysis
[14][15]
By using Cash Flow and other financial indicators, giving decision processes are observed
Sensitivity Analysis and Cash Flow
[16]
0-1 goal programming method was used to determine efficient information technology for a hospital
0-1 Goal Programming
[17]
IT investment are evaluated by using DEA Contrarian investment strategy with DEA
Data Envelope Analysis
[18][19]
Calculation of Net Cash Flow and evaluation of investment alternativesCash Flow and
ROI, Net Present Value
[20]
Investment of production technologyNeural
Networks[21]
Selection of investment project portfolioInteger Linear Programing
[22]
By using Expert System decision support system is development in catering firm
Expert System [23]
On the other hand, there are so many evaluation criteria’s for region, country and GSM
operators selection, which are presented in literature. These are summarized in Table 2.
Topic/Scope Main Criteria’s Sub Criteria’s Reference
Selection of suitable production technology
Strategic Financial PositionGovernment SupportMarket Position
[4]Tactical
FlexibilityMaterial HandlingHuman ResourceDesignQuality
Monitoring Organization CostFacility CostProduction Cost
Foreign investment analysis
Global ConcentrationNumber of CompetitorsGlobal Concentration RateRivalry Rate
[5]
Global Synergy
Global Economy of ScopeKnow-How SharingMarket SharingR&D’s Source SharingR&D’s Personnel SharingManufacturing Personnel SharingMarketing Personnel SharingLogistics System Sharing
Global Strategic Motivation Availability of Strike the Global CompetitorsAdaptation of Future Markets
Location
Closeness to SourcesCloseness to MarketsCultural DifferencesDifferences in Economic Conditions
Competitiveness
Market Share BalanceNumber of Local CompetitorsRatio Between Fix Costs and Value AddedCost of Third Party Changing
Selecting suitable production facility
Closeness to customer
[9]
Infrastructure
Quality of human resource
Free Trade Areas
Advantages of rivalry
Market share forecasting in mobile communication
Advertising
CampaignAdvertising PeriodAdvertising EffectEnvironment Effect
[24]PricingSame GSMDifferent GSMWAP-GPRS
Network Network CoverageNetwork Problems
Brand ImageReliabilityCustomer CareCampaign Sustainability
Table 2: Evaluation Criteria’s for Region, Country and GSM Operators Selection
3. Methodology
In this study, for selecting most suitable GSM operator partners, 4 main steps are followed. These are;
1st Step: To determine region evaluation criteria’s priority coefficients (RECPC).
2nd Step: To determine country evaluation criteria’s priority coefficients (CECPC).
3rd Step: To determine GSM operator evaluation criteria’s priority coefficients (GOECPC).
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4th Step: To determine GSM operator’s scoring (GOS), ranking and select the best one.
No Type Name Description Reference
AMain
CriteriaINPUT Human resource inputs [5]
1Sub
Criteria
Characteristic of
Labor Force
General human resource characteristic and
behaviors in region
[3], [4], [5], [9], Expert
Advice
2Sub
Criteria
Characteristic of
Customers
General customer characteristic and
behaviors in region[5], [9], Expert Advice
BMain
CriteriaECONOMIC Basic economical criteria’s in region [3], [5], Expert Advice
1 Sub Criteria
Inflation RatesGeneral and/or average inflation rate in
region[5], Expert Advice
2 Sub Criteria
FTAs (Free
Trade
Agreement)
Current situation, number and efficiency of
FTAs in region[4], [9], Expert Advice
3 Sub Criteria
Political &
Economic
Stability
Region ’s current political and economic
situation[4], Expert Advice
CMain
Criteria
CONDUCTING
BUSINESS
COMPETENCY
Main business related topics in region [4], Expert Advice
1 Sub Criteria
Starting
Business Competency
Starting conditions to business in region [4], Expert Advice
2 Sub Criteria
Doing Business
CompetencyDoing business conditions in region [4], Expert Advice
3 Sub Criteria
Competitors
Situation
Numbers and effectiveness of competitors
in region[5],[9],Expert Advice
4 Sub Criteria
FDI (Foreign
Direct
Investment)
Supports
Degree of FDI [3], [4], Expert Advice
5 Sub Criteria
Regulation
LawsLaws and regulation degree in region [4], Expert Advice
- 1st Step: In this step, region evaluation criteria (REC) are determined according the literature review an expert interviews as shown in Table 3.
Table 3: Main and sub criteria are for region evaluation.
AHP decision tree has built as shown Figure 1. By using AHP model [24], RECPC is determined and, for selection of the best GSM operators, results are used in 4th Step.
4
1 Characteristic of Labor Force 1 Inflation Rates 1 Starting Business Competency2 Characteristic of Customers 2 FTAs(Free Trade Agreement) 2 Doing Business Competency
3 Political & Economic Stability 3 Competitors Situation4 FDI(Foreing Direct Investment) Supports5 Regulation Laws
Africa AmericasAsia
PacificEurope: Eastern
Europe: Western
Middle East USA/Canada
ALT
ER
NA
TIV
ES
SU
BC
RIT
ER
IAChose the best region for investment
GO
AL
CR
ITE
RIA
INPUT ECONOMIC CONDUCTING BUSINESS COMPETENCY
Figure 1: AHP model for region selection
- 2nd Step: In this step, country evaluation criteria (CEC) are determined according the literature review an expert interviews as shown in Table 4.
Table 4: Country Evaluation CriteriaNo Name Time Period Unit Reference
1 Population 2008 million person [5], Expert Advice2 GDP 2008 million $ [5], Expert Advice
3 GDP per capita 2008 $/person [5], Expert Advice
4 # of Credit Cards in the country 2008 million unitExpert Advice
5 # of Debit Cards in the Country 2008 million unitExpert Advice
6 Total # of Cards in the Country 2008 million unitExpert Advice
7 # of CC Transactions / year 2008 million unitExpert Advice
8 # of DC Transactions / year 2008 million unitExpert Advice
9 Total # of Transactions / year 2008 million unitExpert Advice
10 Credit Card Transaction Volume / year 2008 billion $Expert Advice
11 Debit Card Transaction Volume / year 2008 billion $Expert Advice
12 Total Card Transaction Volume / year 2008 billion $Expert Advice
13 # of Payments per capita 2008 unit/personExpert Advice
14 Payment per capita 2008 $/personExpert Advice
15 Debit Cards Usability for e-commerce 2008 -Expert Advice
16 # of POS Terminals 2008 unitExpert Advice
17 # of Mobile Cellular Phone 2008 million unit[15], Expert Advice
18 Mobile Telecommunication Penetration Rate 2008 -[5], [15], Expert Advice
19 Total Mobile Cellular Subscribers 2008 unit[5], [15], Expert Advice
20 Total Fixed Line Telephone Subscribers 2008 unit[5], [15], Expert Advice
21 Total Telephone Subscribers 2008 unit[5], [15], Expert Advice
Source: [26], [27], [28]
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CEC are classified under some main criteria’s such as Obtainable, Usability and Representative. Then AHP decision tree has built as shown Figure 2. By using AHP model CECPC is determined and, for selection of the best GSM operators, results are used in 4th
Step.
Population
GDPGDP per
capita
# of Credit Cards in the
country
# ofDebit Cards in
the Country
Total # of Cards in the Country
# of CC Transactions /
year
# ofDC Transactions
/ year)
Total # of Transactions /
year
Credit Card Transaction
Volume / year
Debit Card Transaction
Volume / year
Total Card
Transaction
Volume / year
# of of Payments per
capita( / year )
Payment per capita
( / year )
Debit Cards Usability for e-
commerce
# of POS Terminals
# of Mobile Cellular Phone
Mobile Telecommunication Penetration
Rate
Total Mobile Cellular
Subscribers
Total Fixed Line Telephone
Subscribers
Total Telephone
Subscribers
ALT
ER
NA
TIV
ES
GO
AL
Chose the best data which represent to counries' characteristics.
CR
ITE
RIA
Obtainable Usability Representative
Figure 2: AHP model for country evaluation criteria’s
Main criteria for evaluating CSC are;
Obtainable: Relevant evaluation for criteria about how providing criteria is difficult
than others.
Usability: Evaluating a relationship between criteria and investment analysis
according to presentation level to alternatives.
Representative: Evaluating a relationship between criteria and investment analysis
according to importance level to alternatives.
- 3rd Step: In this step, GSM operator evaluation criteria (GOEC) are determined according the literature review an expert interviews as shown in Table 5.
Table 5: Criteria’s for GSM operator evaluation.
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Source: [29]
GOEC are classified under some main criteria’s such as Obtainable, Usability and Representative (also used in 2nd Step).
Then AHP decision tree has built as shown Figure 3. By using AHP model GECPC is determined and, for selection of the best GSM
operators, results are used in 4th Step.
Total # of Subscribers
# of Prepaid Subscribers
# of PostpaidSubscribers
Market Share Blended ARPU Prepaid ARPU
Postpaid ARPUA
LTE
RN
AT
IVE
SG
OA
L
Chose the best data which represent to GSM Operators' characteristics.
CR
ITE
RIA
Obtainable Usability Representative
Figure 3: AHP model for GSM operator criteria’s evaluation
- 4th Step: In this final step, by using 3.1 formula, each GSM operators score (GOS) is calculated by using coefficients which are calculated in first three steps.
For calculation this formulation is used:
∑a
❑
GOS a=∑b
❑
RECPCb x [(∑c
❑
CECPCc) x (∑d
❑
CCNSDd)+(∑e
❑
GOECPCe) x (∑a
❑
GOCNSDa)] (3.1)
Detailed information about formulation is given;
GOS = GSM Operator Score RECPC = Region Evaluation Criteria’s Priority Coefficients CECPC = Country Evaluation Criteria’s Priority Coefficients CCNSD = Country Criteria Normalized Secondary Data GOECPC = GSM Operator evaluation criteria’s priority coefficients GOCNSD = GSM Operator Criteria Normalized Secondary Data
Indexes are;
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No Name DescriptionTime
PeriodUnit Reference
1Total # ofSubscribers
Total subscription number 2008 person [5], Expert Advice
2# of PrepaidSubscribers
Total prepaid subscription number
2008 person [5], Expert Advice
3# of PostpaidSubscribers
Total postpaid subscription number
2008 person [5], Expert Advice
4 Market Share Market share 2008 % [5], [15], Expert Advice
5 Blended ARPU Total ARPU 2008 $/person [15], Expert Advice
6 Prepaid ARPU Prepaid ARPU 2008 $/person [15], Expert Advice
7 Postpaid ARPU Postpaid ARPU 2008 $/person [15], Expert Advice
a:GSM operators in the world
a=1,2,…,656 (USA-1,ING-2 etc.)
b=Regions in the world
b=1,2,..,7 (Africa, Americas, Asia Pacific, Europe: Eastern, Europe: Western, Middle East, USA/Canada)
c= Country evaluation criteria’s
c=1,2,….,21 (Population (million), ….. , Total Mobile Cellular Subscribers).
d=County in the world
d=1,2,..,222 (ABD, China…, Turkey)
e=GSM operator evaluation criteria
e=1,2,..,7 (Total # of Subscribers, … , Prepaid ARPU).
4. Implementation
As mentioned in methodology section, four main steps have been applied.
End of 1st Step, to determine 7 region evaluation criteria’s priority coefficients (RECPC) AHP decision tree has built as shown Figure 1.
In this process, ten experts’ cross comparison matrix are used and, by taking results’ geometric average for each RECPC is calculated.
After all expert’ evolution, Europe: Western has the highest coefficient by 0,254 (See Table 6)
Table 6: Evaluation of regions
Relative Weighted(RECPC)
Europe: Western 0,254
Europe: Eastern 0,252
USA/Canada 0,153
Middle East 0,136
Asia & Pacific 0,095
Americas 0,067Africa 0,038
SUM 1,00
End of 2nd Step, to determine 222 country evaluation criteria’s priority coefficients (CECPC) AHP decision tree has built as shown Figure 2.
In this process, ten experts’ cross comparison matrix are used and, by taking results’ geometric average for each CECPC is calculated.
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After all expert’ evolution, Total Telephone Subscribers has the highest coefficient by 0,117 (See Table 7).
Table 7: Evaluation of country evaluation criteria’s
Relative Weighted(CECPC
Total Telephone Subscribers 0,117Total Mobile Cellular Subscribers 0,102Mobile Telecommunication Penetration Rate 0,092# of Mobile Cellular Phone 0,079Total Fixed Line Telephone Subscribers 0,073# of POS Terminals 0,051Debit Cards Usability for e-commerce 0,045Population 0,039Payment per capita($)( / year ) 0,033# of Payments per capita( / year ) 0,033Credit Card Transaction Volume / year 0,032Debit Card Transaction Volume($) / year (billion) 0,031GDP per capita 0,027Total # of Transactions / year 0,026Total Card Transaction Volume / year 0,027GDP 0,027# DC Transactions / year (million) 0,019Total # of Cards in the Country 0,018# of CC Transactions / year 0,017# of Credit Cards in the country 0,016# of Debit Cards in the Country 0,015
SUM 1,000
End of 3rd Step, to determine 656 GSM operators evaluation criteria’s priority coefficients (GOECPC) AHP decision tree has built as shown Figure 3.
In this process, ten experts’ cross comparison matrix are used and, by taking results’ geometric average for each GOECPC is calculated.
After all expert’ evolution, Prepaid ARPU has the highest coefficient by 0,305 (See Table 8).
Table 8: Evaluation of GSM operator evaluation criteria’s
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Relative Weighted
(GOECPC)
Prepaid ARPU 0,305
Blended ARPU 0,191
Postpaid ARPU 0,184
# of Prepaid Subscribers 0,105
# of Postpaid Subscribers 0,072
Total # of Subscribers 0,071Market Share 0,071
SUM 1,000
End of 4rd Step, 656 GSM operator’ score has been calculated by using Equation 2.1. Then each GSM operator’s score divided by all GSM operator’s total score, scores have been normalized by percentage. After the all process, 656 GSM operators have been ranking by normalized score, and the best 5 GSM operators, which are in different countries, have been selected for investment alternatives. Results are shown in Table 9.
In summary, for investment;- USA-1- CHI-1- UK-1- FR-1- IT-1
are chosen.
Table 9: Score and ranking of chosen GSM operators
RankingScore
(GOS)
Normalized
ScoreRegion Country
GSM
OperatorDecision
1 0,023 1,93% USA/Canada USA USA-1 √
2 0,023 1,89% USA/Canada USA USA-2
3 0,022 1,86% USA/Canada USA USA-3
4 0,022 1,86% USA/Canada USA USA-4
5 0,022 1,80% USA/Canada USA USA-5
6 0,021 1,79% USA/Canada USA USA-6
7 0,021 1,79% USA/Canada USA USA-7
8 0,021 1,78% USA/Canada USA USA-8
9 0,021 1,78% USA/Canada USA USA-9
10 0,021 1,78% USA/Canada USA USA-10
11 0,021 1,77% USA/Canada USA USA-11
12 0,013 1,08% Asian Pacific China CHI-1 √
13 0,012 1,04% Europe: West England UK-1 √
14 0,012 1,02% Europe: West England UK-1
15 0,012 1,01% Europe: West England UK-2
16 0,012 1,01% Europe: West England UK-3
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17 0,011 0,95% Asian Pacific China CHI-2
18 0,010 0,84% Europe: West France FR-1 √
19 0,010 0,83% Europe: West England UK-4
20 0,010 0,83% Europe: West France FR-2
21 0,010 0,81% Europe: West Italia IT-1 √
5. Conclusion and Future ResearchThe purpose of study is to propose and selection system, will provide a comprehensive
approach for selecting the best GSM operator for Call Center, is selling GSM operator’s prepaid minutes, investment. Detailed methodology has been set in the research. On the other hand, this study introduces some finding and future research. These are listed below:
- In investment planning and analysis, not only quantitative factors are looking for, but also qualitative factors are analyzed carefully.
- When analyzing a country, not only general indicators about country, such as population, have been evaluated, but also specific factors, which are related in investment, must be evaluated.
- To analyze a GSM company, not only general criteria has been evaluated, such as Total Subscriber, bur also investment related criteria’s, such as revenue per user, must be evaluated.
- In investment planning and analyzing process, evaluating only regional based criteria’, can be give wrong results. Because of that, country and GSM based criteria’s must be evaluated also.
As stated in research, findings are given for managers and researchers for implementation and/or further research.
This paper prepared with only one firm expert and their expectations. In the future more than one firm’s expert may join this methodology and therefore results should be generalized.
On the other hand, this study can be carried out by using Fuzzy AHP, in order to eliminate unknown parameters in strategic decision support process.
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