GSM Operator Selection for a Call Center Investment by Using AHP

Ozcan Cavusoglu, Mustafa Canolca, Demet Bayraktar,cavusogluozcan@yahoo.com, canolcamc@yahoo.com; demet.bayraktar@itu.edu.trIstanbul 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.

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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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