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Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz

Year 2020, Volume: 15 Issue: 57, 72 - 83, 31.01.2020

Mikail Kar

https://doi.org/10.19168/jyasar.606270

Abstract

Bu çalışmada Türkiye
Mobil Telekomünikasyon Piyasası’ndaki ağ dışsallıklarının varlığı ve etkileri
analiz edilmektedir. Ampirik analizde piyasa talebini ve piyasa fiyatını
dikkate alan dört farklı model Türkiye’deki mobil operatörlere ait
2005q1-2019q1 dönemleri arasındaki panel veriler kullanılarak dinamik ortak
korelasyonlu etkiler (DCCE) tahmincisi yardımıyla tahmin edilmiştir. Elde
edilen sonuçlar talep ve fiyatların belirlenmesinde ağ dışsallıklarının etkili
olduğunu göstermektedir. Sonuçlara göre geçmiş dönemdeki ağa katılma talebinde
%1’lik bir artış mevcut dönemdeki ağa katılma talebini yaklaşık %0.3
artırırken, piyasa fiyatını yaklaşık %2 artırmaktadır. Geçmiş dönemdeki ağı
kullanma talebinde meydana gelecek %1’lik bir artış mevcut dönemdeki ağı
kullanma talebini %0.7 artırırken piyasa fiyatını yaklaşık %1.1 artırmaktadır.
Ayrıca geçmiş dönemdeki piyasa yoğunlaşmasında meydana gelecek %1’lik bir
artışın mobil iletişim talebini %0.1 ile %0.7 arasında, piyasa fiyatını
ise  %2.5 ile %3 arasında artıracağı
tespit edilmiştir.

Keywords

Ağ Dışsallıkları Mobil Telekomünikasyon Piyasası Mobil İletişim Talebi DCCE Tahmincisi

References

  • Ahuja, G. 2000. “Collaboration Networks, Structural Holes, And Innovation: A Longitudinal Study”. Administrative Science Quarterly, 45 (3): 425-455.
  • Arthur, W. 1996. “Increasing Returns And The New World of Business”. Harvard Business Review, 74(4): 100-109.
  • Baltagi, B. H., Feng, Q. & Kao, C. 2012. “A Lagrange Multiplier Test For Cross-Sectional Dependence In A Fixed Effects Panel Data Model”. Journal of Econometrics, 170:164-177.
  • Baraldi, A. L. 2012. “The Size Of The Critical Mass As A Function Of The Strength Of Network Externalities: A Mobile Telephone Estimation”. Economics of Innovation and New Technology, 21(4), 373-396.
  • Birke, D., & Swann, G. M. P. 2006. “Network Effects And The Choice Of Mobile Phone Operator”. Journal of Evolutionary Economics, 16(1-2): 65-84.
  • Bonardi, J -P. & Durand, R. 2003. “Managing Network Effects In High-Tech Markets”. Academy of Management Executive, 17 (4): 40-52.
  • Breusch, T. S. & Pagan, A. 1980. “The Lagrange Multiplier Test And Its Applications To Model Specification In Econometrics”. The Review of Economic Studies, 47(1): 239-253.
  • Brynjolfsson, E., & Kemerer, C. 1996. “Network Externalities In Microcomputer Software: An Econometric Analysis Of The Spreadsheet Market”. Management Science, 42: 1627-1647.
  • BTK, 2019a. https://www.btk.gov.tr/pazar-verileri (20.07.2019).
  • BTK, 2019b. Türkiye Elektronik Haberleşme Sektörü Pazar Verileri Raporu, https://www.btk.gov.tr/uploads/pages/pazar-verileri/2019-1-ceyrekraporu-kurumdisi-5d3579a08c809.pdf (20.07.2019).
  • Candogan, O., Bimpikis, K., & Ozdaglar, A. 2012. “Optimal Pricing In Networks With Externalities”. Operations Research, 60(4): 883-905.
  • Chudik, A & Pesaran, M.H. 2015. “Common Correlated Effects Estimation Of Heterogeneous Dynamic Panel Data Models With Weakly Exogenous Regressors”. Journal of Econometrics, 188:393-420.
  • Church, J., Gandal, N., & Krause, D. 2002. “Indirect Network Effects And Adoption Externalities”. Foerder Institute for Economic Research. Working Paper 02-30.
  • Clements, M. 2004. “Direct And İndirect Network Effects Are They Equivalent?”. International Journal of Industrial Organization, 22: 633-645.
  • Dickey, D. A. & Fuller, W. A. 1979. “Distribution Of The Estimators For Autoregressive Time Series With A Unit Root”. Journal of the American Statistical Association, 74:427-431.
  • Doganoglu, T. & Gryzbowski, L. 2007. “Estimating Network Effects in the Mobile Telephony in Germany”. Information Economics and Policy, 19 (1): 65-79.Economides N., & Himmelberg C. 1995. “Critical Mass And Network Size With Application To The US Fax Market”. Stern School of Business, New York University 'LVFXVVLRQ 3DSHU EC-95-11.
  • Fainmesser, I. P. & Galeotti, A. 2016. “Pricing Network Effects: Competition”. Johns Hopkins Carey Business School, Research Paper No. 17-08.
  • Farrell, J. &Saloner, G. 1985. “Standardization, Compatibility, and Innovation”. RAND Journal of Economics, 16 (1): 70–83.
  • Farrell, J., & Klemperer, P. 2007. “Co-Ordination And Lock-In: Competition With Switching Costs And Network Effects”. in M. Armstrong and R. Porter (eds.) Handbook of Industrial Organization, Vol.3, Elsevier.
  • Frels, J.K., Shervani, T. & Srivastava, R.K. 2003. “The Integrated Networks Model: Explaining Resource Allocations In Network Markets”. Journal of Marketing, 67 (January): 29–45.
  • Fuentelsaz, L., Maicas, J.P. & Polo, Y. 2010. “Switching Costs, Network Effects, and Competition in the European Mobile Telecommunications Industry”. Information Systems Research, Forthcoming.
  • Gallaugher, J., & Wang, Y. 2002. “Understanding Network Effects In Software Markets: Evidence From Web Server Pricing”. MIS Quarterly, 26: 303-327.
  • Gandal, N. 1995. “Competing Compatibility Standards And Network Externalities In The PC Software Market”. Review of Economics and Statistics, 77: 599-608.
  • Goolsbee, A. & Klenow, P. 1999. "Evidence On Learning And Network Externalities In The Diffusion Of Home Computers." National Bureau of Economic Research, Working Paper #7329.
  • Grajek M. 2002. “Identification of Network Externalities in Markets for NonDurables”, Wissenschaftszentrum Berlin, Discussion Paper FS IV 02-32.
  • Grajek M. 2003. “Estimating Network Effects And Compatibility In Mobile Telecommunication”,. Wissenschaftszentrum Berlin, Discussion Paper SP II 2003-26.
  • Grajek, M. 2010. “Estimating Network Effects and Compatibility: Evidence from the Polish mobile market”. Information Economics and Policy, 22(2): 130-143.
  • Jang, S.-L., Dai, S.-C. & Sung, S. 2005. “The Pattern And Externality Effect Of Diffusion Of Mobile Telecommunications: The Case Of The OECD And Taiwan”. Information Economics and Policy, 17: 133-148.
  • Kar, M . 2019. "Characteristics Of Mobile Communication Demand: The Case Of Turkey". Bolu Abant İzzet Baysal Üniversitesi Sosyal Bilimler Enstitüsü Dergisi, 19: 327-345
  • Karaçuka, M. 2009. “Türk Mobil Telekomünikasyon Piyasalarında Firmaların Talep Özelliklerinin Belirleyicileri”. Dokuz Eylül Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi, 24(1): 1-13.
  • Katz, M. & Shapiro, C. 1985. “Network Effect, Competition, and Compatibility”. American Economic Review, 75: 424-440.
  • Katz, M.L., & Shapiro, C. 1994. “System Competition And Network Effects”. Journal of Economic Perspectives, 8: 93–115.
  • Kim, H. S., & Kwon, N. 2003. “The Advantage Of Network Size In Acquiring New Subscribers: A Conditional Logit Analysis Of The Korean Mobile Telephony Market”. Information Economics and Policy, 15(1): 17-33.
  • Liebowitz, S. 2002. Re-Think The Network Economy: The True Forces That Drive The Digital Marketplace. New York: AMACOM.
  • Liebowitz, S.J., & Margolis, S.E. 1994. “Network Externality: An Uncommon Tragedy”. Journal of Economic Perspectives, 8: 133–150.
  • Maicas, J.P., Polo, Y. & Sese, F.J. 2009a. “The Role Of (Personal) Network Effects And Switching Costs In Determining Mobile Users’ Choice”. Journal of Information Technology, 24 (2): 160-171.
  • Maicas, J.P., Polo, Y. & Sese, F.J. 2009b. “Reducing the Level of Switching Costs in Mobile Communications: The Case of Mobile Number Portability”. Telecommunications Policy, 33 (9): 544-554.
  • McIntyre, D.P. & Subramaniam, M. 2009. “Strategy in Network Industries: A Review and Research Agenda”. Journal of Management, 35 (6): 1494-1517.
  • Ohashi, H. 2003. "The Role of Network Effects in the U.S. VCR Market, 1978-1986". Journal of Economics and Management Strategy, 12(4): 447-494.
  • Pesaran, H., Ullah, A. & Yamagata, T. 2008. “A Bias‐Adjusted LM Test Of Error Cross‐Section Independence”. The Econometrics Journal, (11): 105-127.
  • Pesaran, H. 2004. “General Diagnostic Tests For Cross Section Dependence in Panels”. University of Cambridge, Working Paper, CWPE 0435.
  • Pesaran, H. 2007. “A Simple Panel Unit Root Test In The Presence Of Cross-Section Dependence”. Journal of Applied Econometrics, 22(2): 265-312.
  • Rohlfs, J. (1974). “A Theory Of İnterdependent Demand For A Communications Service”. Bell Journal of Economics, 5: 16–37.
  • Schilling, M. A. 2002. “Technology Success and Failure in Winner-Take-All Markets: The Impact of Learning Orientation, Timing, and Network Externalities”. The Academy of Management Journal, 45(2):387-398.
  • Shankar, V., & Bayus, B. 2002. “Network Effects And Competition: An Empirical Analysis Of The Home Video Game Industry”. Strategic Management Journal, 24: 375-384.
  • Shapiro, C., & Varian, H.R. 1998. Information Rules – A Strategic Guide to the Network Economy. Harvard Business School Press, Boston.
  • Shew, W. 1994. “Regulation, Competition And Prices İn Cellular Telephony”. The American Enterprise Institute for Public Policy Research, Working Paper no. 4329,
  • Sobolewski, M. & Czajkowsi, M. 2012. “Network Effects And Preference Heterogeneity İn The Case Of Mobile Telecommunications Markets”. Telecommunications Policy, 36: 197-211.
  • Srinivasan, R., Lilien, G.L & Rangaswamy, A. 2004. “First In, First Out? The Effects of Network Externalities on Pioneer Survival”. Journal of Marketing, 68 (January): 41– 58.
  • Suarez, F. 2005. “Network Effects Revisited: The Role Of Strong Ties In Technology Selection”. Academy of Management Journal, 48: 710-722.
  • Swann, G.P. 2002. “The Functional Form of Network Effects”. Information Economics and Policy, 14, 417–429.
  • Westerlund, J. 2008. “Panel Cointegration Tests of The Fisher Effect”. Journal of Applied Econometrics, 23(2): 193-223.

Network Externalities: An Empirical Analysis For The Turkish Mobile Communications Market

Year 2020, Volume: 15 Issue: 57, 72 - 83, 31.01.2020

Mikail Kar

https://doi.org/10.19168/jyasar.606270

Abstract

In this study, the existence
and effects of network externalities in Turkish Mobile Telecommunications
Market is analyzed. In empirical analysis, four different models, both taking
market demand and market price into account, were estimated using panel data
from the 2005q1-2019q1 periods of mobile operators in Turkey with the help of
dynamic common correlated effects (DCCE) estimator. The results show that
network externalities are effective in determining demand and prices. According
to the results, a 1% increase in the demand for joining the network in the past
period increases the demand for joining the network in the current period by
about 0.3%, while increases the market price by about 2%. A 1% increase in the
demand to use the network in the past period increases the demand to use the
network in the current period by 0.7%, increases the market price by about
1.1%. Furthermore, it was determined that a 1% increase in market concentration
in the past period would increase the demand for mobile communication between 0.1%
and 0.7% and increase the market price between 2.5% and 3%.

Keywords

Network Externalities Mobile Telecommunications Market Demand For Mobile Communications DCCE Estimator

References

  • Ahuja, G. 2000. “Collaboration Networks, Structural Holes, And Innovation: A Longitudinal Study”. Administrative Science Quarterly, 45 (3): 425-455.
  • Arthur, W. 1996. “Increasing Returns And The New World of Business”. Harvard Business Review, 74(4): 100-109.
  • Baltagi, B. H., Feng, Q. & Kao, C. 2012. “A Lagrange Multiplier Test For Cross-Sectional Dependence In A Fixed Effects Panel Data Model”. Journal of Econometrics, 170:164-177.
  • Baraldi, A. L. 2012. “The Size Of The Critical Mass As A Function Of The Strength Of Network Externalities: A Mobile Telephone Estimation”. Economics of Innovation and New Technology, 21(4), 373-396.
  • Birke, D., & Swann, G. M. P. 2006. “Network Effects And The Choice Of Mobile Phone Operator”. Journal of Evolutionary Economics, 16(1-2): 65-84.
  • Bonardi, J -P. & Durand, R. 2003. “Managing Network Effects In High-Tech Markets”. Academy of Management Executive, 17 (4): 40-52.
  • Breusch, T. S. & Pagan, A. 1980. “The Lagrange Multiplier Test And Its Applications To Model Specification In Econometrics”. The Review of Economic Studies, 47(1): 239-253.
  • Brynjolfsson, E., & Kemerer, C. 1996. “Network Externalities In Microcomputer Software: An Econometric Analysis Of The Spreadsheet Market”. Management Science, 42: 1627-1647.
  • BTK, 2019a. https://www.btk.gov.tr/pazar-verileri (20.07.2019).
  • BTK, 2019b. Türkiye Elektronik Haberleşme Sektörü Pazar Verileri Raporu, https://www.btk.gov.tr/uploads/pages/pazar-verileri/2019-1-ceyrekraporu-kurumdisi-5d3579a08c809.pdf (20.07.2019).
  • Candogan, O., Bimpikis, K., & Ozdaglar, A. 2012. “Optimal Pricing In Networks With Externalities”. Operations Research, 60(4): 883-905.
  • Chudik, A & Pesaran, M.H. 2015. “Common Correlated Effects Estimation Of Heterogeneous Dynamic Panel Data Models With Weakly Exogenous Regressors”. Journal of Econometrics, 188:393-420.
  • Church, J., Gandal, N., & Krause, D. 2002. “Indirect Network Effects And Adoption Externalities”. Foerder Institute for Economic Research. Working Paper 02-30.
  • Clements, M. 2004. “Direct And İndirect Network Effects Are They Equivalent?”. International Journal of Industrial Organization, 22: 633-645.
  • Dickey, D. A. & Fuller, W. A. 1979. “Distribution Of The Estimators For Autoregressive Time Series With A Unit Root”. Journal of the American Statistical Association, 74:427-431.
  • Doganoglu, T. & Gryzbowski, L. 2007. “Estimating Network Effects in the Mobile Telephony in Germany”. Information Economics and Policy, 19 (1): 65-79.Economides N., & Himmelberg C. 1995. “Critical Mass And Network Size With Application To The US Fax Market”. Stern School of Business, New York University 'LVFXVVLRQ 3DSHU EC-95-11.
  • Fainmesser, I. P. & Galeotti, A. 2016. “Pricing Network Effects: Competition”. Johns Hopkins Carey Business School, Research Paper No. 17-08.
  • Farrell, J. &Saloner, G. 1985. “Standardization, Compatibility, and Innovation”. RAND Journal of Economics, 16 (1): 70–83.
  • Farrell, J., & Klemperer, P. 2007. “Co-Ordination And Lock-In: Competition With Switching Costs And Network Effects”. in M. Armstrong and R. Porter (eds.) Handbook of Industrial Organization, Vol.3, Elsevier.
  • Frels, J.K., Shervani, T. & Srivastava, R.K. 2003. “The Integrated Networks Model: Explaining Resource Allocations In Network Markets”. Journal of Marketing, 67 (January): 29–45.
  • Fuentelsaz, L., Maicas, J.P. & Polo, Y. 2010. “Switching Costs, Network Effects, and Competition in the European Mobile Telecommunications Industry”. Information Systems Research, Forthcoming.
  • Gallaugher, J., & Wang, Y. 2002. “Understanding Network Effects In Software Markets: Evidence From Web Server Pricing”. MIS Quarterly, 26: 303-327.
  • Gandal, N. 1995. “Competing Compatibility Standards And Network Externalities In The PC Software Market”. Review of Economics and Statistics, 77: 599-608.
  • Goolsbee, A. & Klenow, P. 1999. "Evidence On Learning And Network Externalities In The Diffusion Of Home Computers." National Bureau of Economic Research, Working Paper #7329.
  • Grajek M. 2002. “Identification of Network Externalities in Markets for NonDurables”, Wissenschaftszentrum Berlin, Discussion Paper FS IV 02-32.
  • Grajek M. 2003. “Estimating Network Effects And Compatibility In Mobile Telecommunication”,. Wissenschaftszentrum Berlin, Discussion Paper SP II 2003-26.
  • Grajek, M. 2010. “Estimating Network Effects and Compatibility: Evidence from the Polish mobile market”. Information Economics and Policy, 22(2): 130-143.
  • Jang, S.-L., Dai, S.-C. & Sung, S. 2005. “The Pattern And Externality Effect Of Diffusion Of Mobile Telecommunications: The Case Of The OECD And Taiwan”. Information Economics and Policy, 17: 133-148.
  • Kar, M . 2019. "Characteristics Of Mobile Communication Demand: The Case Of Turkey". Bolu Abant İzzet Baysal Üniversitesi Sosyal Bilimler Enstitüsü Dergisi, 19: 327-345
  • Karaçuka, M. 2009. “Türk Mobil Telekomünikasyon Piyasalarında Firmaların Talep Özelliklerinin Belirleyicileri”. Dokuz Eylül Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi, 24(1): 1-13.
  • Katz, M. & Shapiro, C. 1985. “Network Effect, Competition, and Compatibility”. American Economic Review, 75: 424-440.
  • Katz, M.L., & Shapiro, C. 1994. “System Competition And Network Effects”. Journal of Economic Perspectives, 8: 93–115.
  • Kim, H. S., & Kwon, N. 2003. “The Advantage Of Network Size In Acquiring New Subscribers: A Conditional Logit Analysis Of The Korean Mobile Telephony Market”. Information Economics and Policy, 15(1): 17-33.
  • Liebowitz, S. 2002. Re-Think The Network Economy: The True Forces That Drive The Digital Marketplace. New York: AMACOM.
  • Liebowitz, S.J., & Margolis, S.E. 1994. “Network Externality: An Uncommon Tragedy”. Journal of Economic Perspectives, 8: 133–150.
  • Maicas, J.P., Polo, Y. & Sese, F.J. 2009a. “The Role Of (Personal) Network Effects And Switching Costs In Determining Mobile Users’ Choice”. Journal of Information Technology, 24 (2): 160-171.
  • Maicas, J.P., Polo, Y. & Sese, F.J. 2009b. “Reducing the Level of Switching Costs in Mobile Communications: The Case of Mobile Number Portability”. Telecommunications Policy, 33 (9): 544-554.
  • McIntyre, D.P. & Subramaniam, M. 2009. “Strategy in Network Industries: A Review and Research Agenda”. Journal of Management, 35 (6): 1494-1517.
  • Ohashi, H. 2003. "The Role of Network Effects in the U.S. VCR Market, 1978-1986". Journal of Economics and Management Strategy, 12(4): 447-494.
  • Pesaran, H., Ullah, A. & Yamagata, T. 2008. “A Bias‐Adjusted LM Test Of Error Cross‐Section Independence”. The Econometrics Journal, (11): 105-127.
  • Pesaran, H. 2004. “General Diagnostic Tests For Cross Section Dependence in Panels”. University of Cambridge, Working Paper, CWPE 0435.
  • Pesaran, H. 2007. “A Simple Panel Unit Root Test In The Presence Of Cross-Section Dependence”. Journal of Applied Econometrics, 22(2): 265-312.
  • Rohlfs, J. (1974). “A Theory Of İnterdependent Demand For A Communications Service”. Bell Journal of Economics, 5: 16–37.
  • Schilling, M. A. 2002. “Technology Success and Failure in Winner-Take-All Markets: The Impact of Learning Orientation, Timing, and Network Externalities”. The Academy of Management Journal, 45(2):387-398.
  • Shankar, V., & Bayus, B. 2002. “Network Effects And Competition: An Empirical Analysis Of The Home Video Game Industry”. Strategic Management Journal, 24: 375-384.
  • Shapiro, C., & Varian, H.R. 1998. Information Rules – A Strategic Guide to the Network Economy. Harvard Business School Press, Boston.
  • Shew, W. 1994. “Regulation, Competition And Prices İn Cellular Telephony”. The American Enterprise Institute for Public Policy Research, Working Paper no. 4329,
  • Sobolewski, M. & Czajkowsi, M. 2012. “Network Effects And Preference Heterogeneity İn The Case Of Mobile Telecommunications Markets”. Telecommunications Policy, 36: 197-211.
  • Srinivasan, R., Lilien, G.L & Rangaswamy, A. 2004. “First In, First Out? The Effects of Network Externalities on Pioneer Survival”. Journal of Marketing, 68 (January): 41– 58.
  • Suarez, F. 2005. “Network Effects Revisited: The Role Of Strong Ties In Technology Selection”. Academy of Management Journal, 48: 710-722.
  • Swann, G.P. 2002. “The Functional Form of Network Effects”. Information Economics and Policy, 14, 417–429.
  • Westerlund, J. 2008. “Panel Cointegration Tests of The Fisher Effect”. Journal of Applied Econometrics, 23(2): 193-223.
There are 52 citations in total.

Details

Primary Language Turkish
Journal Section Articles
Authors

Mikail Kar 0000-0002-4036-7355

Publication Date January 31, 2020
Published in Issue Year 2020 Volume: 15 Issue: 57

Cite

APA Kar, M. (2020). Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz. Yaşar Üniversitesi E-Dergisi, 15(57), 72-83. https://doi.org/10.19168/jyasar.606270
AMA Kar M. Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz. Yaşar Üniversitesi E-Dergisi. January 2020;15(57):72-83. doi:10.19168/jyasar.606270
Chicago Kar, Mikail. “Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz”. Yaşar Üniversitesi E-Dergisi 15, no. 57 (January 2020): 72-83. https://doi.org/10.19168/jyasar.606270.
EndNote Kar M (January 1, 2020) Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz. Yaşar Üniversitesi E-Dergisi 15 57 72–83.
IEEE M. Kar, “Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz”, Yaşar Üniversitesi E-Dergisi, vol. 15, no. 57, pp. 72–83, 2020, doi: 10.19168/jyasar.606270.
ISNAD Kar, Mikail. “Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz”. Yaşar Üniversitesi E-Dergisi 15/57 (January 2020), 72-83. https://doi.org/10.19168/jyasar.606270.
JAMA Kar M. Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz. Yaşar Üniversitesi E-Dergisi. 2020;15:72–83.
MLA Kar, Mikail. “Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz”. Yaşar Üniversitesi E-Dergisi, vol. 15, no. 57, 2020, pp. 72-83, doi:10.19168/jyasar.606270.
Vancouver Kar M. Ağ Dışsallıkları: Türkiye Mobil İletişim Piyasası İçin Ampirik Bir Analiz. Yaşar Üniversitesi E-Dergisi. 2020;15(57):72-83.
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