Main Article Content
Abstract
Purpose ― The global pandemic COVID-19 has attracted considerable interest from researchers globally. However, there is very little systematic work on the impact of the COVID-19 crisis on the local stock markets. This paper proposes a complex network method that examines the effects of global pandemic COVID-19 on the Pakistan stock market to fill in these gaps.
Methods ― Firstly, correlograms are plotted to inspect the correlation matrices of the overall and two sub-sample periods. Secondly, correlation threshold networks and topological properties are examined for different threshold levels. Finally, this paper uses evolving MSTs to construct a dynamical complex network and presents dynamic centrality measures, normalised tree, and average path lengths.
Findings ― The findings show that COVID-19 related certainty and crisis lead to low volatility and a star-like structure, resulting in a quick flow of information and a strong correlation among the Pakistan stock market.
Implication ― This analysis would help investors and regulators to manage the Pakistan stock market better. In addition, the comprehensive study solely on the Pakistan stock market will be helpful for Pakistan government officials and stock market participants to assess and predict the risks of the Pakistan stock market associated with the global pandemic COVID-19.
Originality ― This paper addresses both classes of the networks. To the best of our knowledge, the static and dynamic evolution of the Pakistan stock market around the global pandemic COVID-19 has not been performed yet.
Keywords
Article Details
Copyright (c) 2022 Bilal Ahmed Memon
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References
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- Albulescu, C. T. (2021). COVID-19 and the United States financial markets’ volatility. Finance Research Letters, 38, 101699. https://doi.org/10.1016/j.frl.2020.101699
- Alexakis, C., Eleftheriou, K., & Patsoulis, P. (2021). COVID-19 containment measures and stock market returns: An international spatial econometrics investigation. Journal of Behavioral and Experimental Finance, 29, 100428. https://doi.org/10.1016/j.jbef.2020.100428
- Ashraf, B. N. (2020a). Economic impact of government interventions during the COVID-19 pandemic: International evidence from financial markets. Journal of Behavioral and Experimental Finance, 27, 100371. https://doi.org/10.1016/j.jbef.2020.100371
- Ashraf, B. N. (2020b). Stock markets’ reaction to COVID-19: Cases or fatalities? Research in International Business and Finance, 54, 101249. https://doi.org/10.1016/j.ribaf.2020.101249
- Aslam, F., Mohmand, Y. T., Ferreira, P., Memon, B. A., Khan, M., & Khan, M. (2020, December). Network analysis of global stock markets at the beginning of the coronavirus disease (Covid-19) outbreak. Borsa Istanbul Review. https://doi.org/10.1016/j.bir.2020.09.003
- Baker, S. R., Bloom, N., Davis, S. J., Kost, K., Sammon, M., & Viratyosin, T. (2020). The unprecedented stock market reaction to COVID-19. The Review of Asset Pricing Studies, 10(4), 742–758. https://doi.org/10.1093/rapstu/raaa008
- Barthélemy, M. (2004). Betweenness centrality in large complex networks. The European Physical Journal B, 38(2), 163–168. https://doi.org/10.1140/epjb/e2004-00111-4
- Cao, J., & Wen, F. (2019). The impact of the cross-shareholding network on extreme price movements: Evidence from China. Journal of Risk, 22(2), 79–102. https://doi.org/10.21314/JOR.2019.423iyj
- Cepoi, C.-O. (2020). Asymmetric dependence between stock market returns and news during COVID-19 financial turmoil. Finance Research Letters, 36, 101658. https://doi.org/10.1016/j.frl.2020.101658
- Chakrabarti, B. K., Chakraborti, A., & Chatterjee, A. (2006). Econophysics and sociophysics: Trends and perspectives. New Jersey: John Wiley & Sons.
- Dimitrios, K., & Vasileios, O. (2015). A network analysis of the Greek stock market. Procedia Economics and Finance, 33, 340–349. https://doi.org/10.1016/S2212-5671(15)01718-9
- Goodell, J. W. (2020). COVID-19 and finance: Agendas for future research. Finance Research Letters, 35, 101512. https://doi.org/10.1016/j.frl.2020.101512
- He, P., Sun, Y., Zhang, Y., & Li, T. (2020). COVID–19’s impact on stock prices across different sectors—An event study based on the Chinese stock market. Emerging Markets Finance and Trade, 56(10), 2198–2212. https://doi.org/10.1080/1540496X.2020.1785865
- Huang, C., Zhao, X., Su, R., Yang, X., & Yang, X. (2020). Dynamic network topology and market performance: A case of the Chinese stock market. Review of Financial Analysis, 76(C), 101782. https://doi.org/10.1002/ijfe.2253
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- Kazemilari, M., Mohamadi, A., Mardani, A., & Streimikis, J. (2019). Network topology of renewable energy companies: minimal spanning tree and sub-dominant ultrametric for the American stock. Technological and Economic Development of Economy, 25(2), 168–187. https://doi.org/10.3846/tede.2019.7686
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- Lee, J. W., & Nobi, A. (2018). State and network structures of stock markets around the global financial crisis. Computational Economics, 51(2), 195–210. https://doi.org/10.1007/s10614-017-9672-x
- Liu, H., Manzoor, A., Wang, C., Zhang, L., & Manzoor, Z. (2020). The COVID-19 outbreak and affected countries stock markets response. International Journal of Environmental Research and Public Health, 17(8). https://doi.org/10.3390/ijerph17082800
- Mantegna, R. N. (1999). Hierarchical structure in financial markets. The European Physical Journal B-Condensed Matter and Complex Systems, 11(1), 193–197.
- Mazur, M., Dang, M., & Vega, M. (2021). COVID-19 and the march 2020 stock market crash. Evidence from S&P1500. Finance Research Letters, 38, 101690. https://doi.org/10.1016/j.frl.2020.101690
- Memon, B. A., & Yao, H. (2019). Structural change and dynamics of Pakistan stock market during crisis: A complex network perspective. Entropy, 21(3), 248. https://doi.org/10.3390/e21030248
- Memon, B. A., & Yao, H. (2021). Correlation structure networks of stock market during terrorism: Evidence from Pakistan. Data Science in Finance and Economics, 1(2), 117–140. https://doi.org/10.3934/DSFE.2021007
- Memon, B. A., Yao, H., Aslam, F., & Tahir, R. (2019). Network analysis of Pakistan stock market during the turbulence of economic crisis. Business, Management and Economics Engineering, 17(2), 269–285. https://doi.org/10.3846/bme.2019.11394
- Memon, B. A., Yao, H., & Tahir, R. (2020). General election effect on the network topology of Pakistan’s stock market: Network-based study of a political event. Financial Innovation, 6(1), 2. https://doi.org/10.1186/s40854-019-0165-x
- Mittal, S., & Sharma, D. (2021). The impact of COVID-19 on stock returns of the Indian healthcare and pharmaceutical sector. Australasian Accounting Business and Finance Journal, 15(1), 5–12. https://doi.org/10.14453/aabfj.v15i1.2
- Narayan, P. K., Devpura, N., & Wang, H. (2020). Japanese currency and stock market—What happened during the COVID-19 pandemic? Economic Analysis and Policy, 68, 191–198. https://doi.org/10.1016/j.eap.2020.09.014
- Onnela, J.-P., Chakraborti, A., Kaski, K., & Kertész, J. (2003). Dynamic asset trees and Black Monday. Physica A: Statistical Mechanics and Its Applications, 324(1), 247–252. https://doi.org/10.1016/S0378-4371(02)01882-4
- Salisu, A. A., Ebuh, G. U., & Usman, N. (2020). Revisiting oil-stock nexus during COVID-19 pandemic: Some preliminary results. International Review of Economics & Finance, 69, 280–294. https://doi.org/10.1016/j.iref.2020.06.023
- Salisu, A. A., Sikiru, A. A., & Vo, X. V. (2020). Pandemics and the emerging stock markets. Borsa Istanbul Review, 20, S40–S48. https://doi.org/10.1016/j.bir.2020.11.004
- Saqlain, M., Munir, M. M., Ahmed, A., Tahir, A. H., & Kamran, S. (2020). Is Pakistan prepared to tackle the coronavirus epidemic? Drugs & Therapy Perspectives, 36(5), 213–214. https://doi.org/10.1007/s40267-020-00721-1
- Takyi, P. O., & Bentum-Ennin, I. (2021). The impact of COVID-19 on stock market performance in Africa: A Bayesian structural time series approach. Journal of Economics and Business, 115, 105968. https://doi.org/10.1016/j.jeconbus.2020.105968
- Tang, Y., Xiong, J. J., Jia, Z.-Y., & Zhang, Y.-C. (2018). Complexities in financial network topological dynamics: Modeling of emerging and developed stock markets. Complexity, 2018, 4680140. https://doi.org/10.1155/2018/4680140
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- Topcu, M., & Gulal, O. S. (2020). The impact of COVID-19 on emerging stock markets. Finance Research Letters, 36, 101691. https://doi.org/10.1016/j.frl.2020.101691
- Waheed, R., Sarwar, S., Sarwar, S., & Khan, M. K. (2020). The impact of COVID-19 on Karachi stock exchange: Quantile-on-quantile approach using secondary and predicted data. Journal of Public Affairs, 20(4), e2290. https://doi.org/https://doi.org/10.1002/pa.2290
- Waris, A., Atta, U. K., Ali, M., Asmat, A., & Baset, A. (2020). COVID-19 outbreak: Current scenario of Pakistan. New Microbes and New Infections, 35, 100681. https://doi.org/10.1016/j.nmni.2020.100681
- Wiliński, M., Sienkiewicz, A., Gubiec, T., Kutner, R., & Struzik, Z. R. (2013). Structural and topological phase transitions on the German Stock Exchange. Physica A: Statistical Mechanics and Its Applications, 392(23), 5963–5973. https://doi.org/10.1016/j.physa.2013.07.064
- Xu, R., Wong, W.-K., Chen, G., & Huang, S. (2017). Topological characteristics of the Hong Kong stock market: A test-based P-threshold approach to understanding Network Complexity. Scientific Reports, 7, 41379. https://doi.org/10.1038/srep41379
- Yao, H., & Memon, B. A. (2019). Network topology of FTSE 100 Index companies: From the perspective of Brexit. Physica A: Statistical Mechanics and Its Applications, 523, 1248–1262. https://doi.org/10.1016/j.physa.2019.04.106
- Zhang, D., Hu, M., & Ji, Q. (2020). Financial markets under the global pandemic of COVID-19. Finance Research Letters, 36, 101528. https://doi.org/10.1016/j.frl.2020.101528
- Zhao, L., Li, W., & Cai, X. (2016). Structure and dynamics of stock market in times of crisis. Physics Letters A, 380(5), 654–666. https://doi.org/10.1016/j.physleta.2015.11.015
- Zhu, S., Kou, M., Lai, F., Feng, Q., & Du, G. (2021). The connectedness of the Coronavirus Disease pandemic in the world: A study based on complex network analysis. Frontiers in Physics, 8. https://doi.org/10.3389/fphy.2020.602075
References
Al-Awadhi, A. M., Alsaifi, K., Al-Awadhi, A., & Alhammadi, S. (2020). Death and contagious infectious diseases: Impact of the COVID-19 virus on stock market returns. Journal of Behavioral and Experimental Finance, 27, 100326. https://doi.org/10.1016/j.jbef.2020.100326
Alam, M. N., Alam, M. S., & Kavita, C. (2020). Stock market response during COVID-19 lockdown period in India: An event study. The Journal of Asian Finance, Economics and Business, 7(7), 131–137. https://doi.org/10.13106/JAFEB.2020.VOL7.NO7.131
Albulescu, C. T. (2021). COVID-19 and the United States financial markets’ volatility. Finance Research Letters, 38, 101699. https://doi.org/10.1016/j.frl.2020.101699
Alexakis, C., Eleftheriou, K., & Patsoulis, P. (2021). COVID-19 containment measures and stock market returns: An international spatial econometrics investigation. Journal of Behavioral and Experimental Finance, 29, 100428. https://doi.org/10.1016/j.jbef.2020.100428
Ashraf, B. N. (2020a). Economic impact of government interventions during the COVID-19 pandemic: International evidence from financial markets. Journal of Behavioral and Experimental Finance, 27, 100371. https://doi.org/10.1016/j.jbef.2020.100371
Ashraf, B. N. (2020b). Stock markets’ reaction to COVID-19: Cases or fatalities? Research in International Business and Finance, 54, 101249. https://doi.org/10.1016/j.ribaf.2020.101249
Aslam, F., Mohmand, Y. T., Ferreira, P., Memon, B. A., Khan, M., & Khan, M. (2020, December). Network analysis of global stock markets at the beginning of the coronavirus disease (Covid-19) outbreak. Borsa Istanbul Review. https://doi.org/10.1016/j.bir.2020.09.003
Baker, S. R., Bloom, N., Davis, S. J., Kost, K., Sammon, M., & Viratyosin, T. (2020). The unprecedented stock market reaction to COVID-19. The Review of Asset Pricing Studies, 10(4), 742–758. https://doi.org/10.1093/rapstu/raaa008
Barthélemy, M. (2004). Betweenness centrality in large complex networks. The European Physical Journal B, 38(2), 163–168. https://doi.org/10.1140/epjb/e2004-00111-4
Cao, J., & Wen, F. (2019). The impact of the cross-shareholding network on extreme price movements: Evidence from China. Journal of Risk, 22(2), 79–102. https://doi.org/10.21314/JOR.2019.423iyj
Cepoi, C.-O. (2020). Asymmetric dependence between stock market returns and news during COVID-19 financial turmoil. Finance Research Letters, 36, 101658. https://doi.org/10.1016/j.frl.2020.101658
Chakrabarti, B. K., Chakraborti, A., & Chatterjee, A. (2006). Econophysics and sociophysics: Trends and perspectives. New Jersey: John Wiley & Sons.
Dimitrios, K., & Vasileios, O. (2015). A network analysis of the Greek stock market. Procedia Economics and Finance, 33, 340–349. https://doi.org/10.1016/S2212-5671(15)01718-9
Goodell, J. W. (2020). COVID-19 and finance: Agendas for future research. Finance Research Letters, 35, 101512. https://doi.org/10.1016/j.frl.2020.101512
He, P., Sun, Y., Zhang, Y., & Li, T. (2020). COVID–19’s impact on stock prices across different sectors—An event study based on the Chinese stock market. Emerging Markets Finance and Trade, 56(10), 2198–2212. https://doi.org/10.1080/1540496X.2020.1785865
Huang, C., Zhao, X., Su, R., Yang, X., & Yang, X. (2020). Dynamic network topology and market performance: A case of the Chinese stock market. Review of Financial Analysis, 76(C), 101782. https://doi.org/10.1002/ijfe.2253
Huo, X., & Qiu, Z. (2020). How does China’s stock market react to the announcement of the COVID-19 pandemic lockdown? Economic and Political Studies, 8(4), 436–461. https://doi.org/10.1080/20954816.2020.1780695
Jia, X., An, H., Sun, X., Huang, X., & Wang, L. (2017). Evolution of world crude oil market integration and diversification: A wavelet-based complex network perspective. Applied Energy, 185, 1788–1798. https://doi.org/10.1016/j.apenergy.2015.11.007
Kazemilari, M., Mohamadi, A., Mardani, A., & Streimikis, J. (2019). Network topology of renewable energy companies: minimal spanning tree and sub-dominant ultrametric for the American stock. Technological and Economic Development of Economy, 25(2), 168–187. https://doi.org/10.3846/tede.2019.7686
Khuntia, S., & Pattanayak, J. K. (2020). Adaptive long memory in volatility of intra-day bitcoin returns and the impact of trading volume. Finance Research Letters, 32, 101077. https://doi.org/10.1016/j.frl.2018.12.025
Kumar, S., & Deo, N. (2013). Analyzing crisis in global financial indices. In F. Abergel, B. K. Chakrabarti, A. Chakraborti, & A. Ghosh (Eds.), Econophysics of Systemic Risk and Network Dynamics (pp. 261–275). Milano: Springer Milan.
Lee, J. W., & Nobi, A. (2018). State and network structures of stock markets around the global financial crisis. Computational Economics, 51(2), 195–210. https://doi.org/10.1007/s10614-017-9672-x
Liu, H., Manzoor, A., Wang, C., Zhang, L., & Manzoor, Z. (2020). The COVID-19 outbreak and affected countries stock markets response. International Journal of Environmental Research and Public Health, 17(8). https://doi.org/10.3390/ijerph17082800
Mantegna, R. N. (1999). Hierarchical structure in financial markets. The European Physical Journal B-Condensed Matter and Complex Systems, 11(1), 193–197.
Mazur, M., Dang, M., & Vega, M. (2021). COVID-19 and the march 2020 stock market crash. Evidence from S&P1500. Finance Research Letters, 38, 101690. https://doi.org/10.1016/j.frl.2020.101690
Memon, B. A., & Yao, H. (2019). Structural change and dynamics of Pakistan stock market during crisis: A complex network perspective. Entropy, 21(3), 248. https://doi.org/10.3390/e21030248
Memon, B. A., & Yao, H. (2021). Correlation structure networks of stock market during terrorism: Evidence from Pakistan. Data Science in Finance and Economics, 1(2), 117–140. https://doi.org/10.3934/DSFE.2021007
Memon, B. A., Yao, H., Aslam, F., & Tahir, R. (2019). Network analysis of Pakistan stock market during the turbulence of economic crisis. Business, Management and Economics Engineering, 17(2), 269–285. https://doi.org/10.3846/bme.2019.11394
Memon, B. A., Yao, H., & Tahir, R. (2020). General election effect on the network topology of Pakistan’s stock market: Network-based study of a political event. Financial Innovation, 6(1), 2. https://doi.org/10.1186/s40854-019-0165-x
Mittal, S., & Sharma, D. (2021). The impact of COVID-19 on stock returns of the Indian healthcare and pharmaceutical sector. Australasian Accounting Business and Finance Journal, 15(1), 5–12. https://doi.org/10.14453/aabfj.v15i1.2
Narayan, P. K., Devpura, N., & Wang, H. (2020). Japanese currency and stock market—What happened during the COVID-19 pandemic? Economic Analysis and Policy, 68, 191–198. https://doi.org/10.1016/j.eap.2020.09.014
Onnela, J.-P., Chakraborti, A., Kaski, K., & Kertész, J. (2003). Dynamic asset trees and Black Monday. Physica A: Statistical Mechanics and Its Applications, 324(1), 247–252. https://doi.org/10.1016/S0378-4371(02)01882-4
Salisu, A. A., Ebuh, G. U., & Usman, N. (2020). Revisiting oil-stock nexus during COVID-19 pandemic: Some preliminary results. International Review of Economics & Finance, 69, 280–294. https://doi.org/10.1016/j.iref.2020.06.023
Salisu, A. A., Sikiru, A. A., & Vo, X. V. (2020). Pandemics and the emerging stock markets. Borsa Istanbul Review, 20, S40–S48. https://doi.org/10.1016/j.bir.2020.11.004
Saqlain, M., Munir, M. M., Ahmed, A., Tahir, A. H., & Kamran, S. (2020). Is Pakistan prepared to tackle the coronavirus epidemic? Drugs & Therapy Perspectives, 36(5), 213–214. https://doi.org/10.1007/s40267-020-00721-1
Takyi, P. O., & Bentum-Ennin, I. (2021). The impact of COVID-19 on stock market performance in Africa: A Bayesian structural time series approach. Journal of Economics and Business, 115, 105968. https://doi.org/10.1016/j.jeconbus.2020.105968
Tang, Y., Xiong, J. J., Jia, Z.-Y., & Zhang, Y.-C. (2018). Complexities in financial network topological dynamics: Modeling of emerging and developed stock markets. Complexity, 2018, 4680140. https://doi.org/10.1155/2018/4680140
Taylor, D., Klimm, F., Harrington, H. A., Kramár, M., Mischaikow, K., Porter, M. A., & Mucha, P. J. (2015). Topological data analysis of contagion maps for examining spreading processes on networks. Nature Communications, 6(1), 7723. https://doi.org/10.1038/ncomms8723
Topcu, M., & Gulal, O. S. (2020). The impact of COVID-19 on emerging stock markets. Finance Research Letters, 36, 101691. https://doi.org/10.1016/j.frl.2020.101691
Waheed, R., Sarwar, S., Sarwar, S., & Khan, M. K. (2020). The impact of COVID-19 on Karachi stock exchange: Quantile-on-quantile approach using secondary and predicted data. Journal of Public Affairs, 20(4), e2290. https://doi.org/https://doi.org/10.1002/pa.2290
Waris, A., Atta, U. K., Ali, M., Asmat, A., & Baset, A. (2020). COVID-19 outbreak: Current scenario of Pakistan. New Microbes and New Infections, 35, 100681. https://doi.org/10.1016/j.nmni.2020.100681
Wiliński, M., Sienkiewicz, A., Gubiec, T., Kutner, R., & Struzik, Z. R. (2013). Structural and topological phase transitions on the German Stock Exchange. Physica A: Statistical Mechanics and Its Applications, 392(23), 5963–5973. https://doi.org/10.1016/j.physa.2013.07.064
Xu, R., Wong, W.-K., Chen, G., & Huang, S. (2017). Topological characteristics of the Hong Kong stock market: A test-based P-threshold approach to understanding Network Complexity. Scientific Reports, 7, 41379. https://doi.org/10.1038/srep41379
Yao, H., & Memon, B. A. (2019). Network topology of FTSE 100 Index companies: From the perspective of Brexit. Physica A: Statistical Mechanics and Its Applications, 523, 1248–1262. https://doi.org/10.1016/j.physa.2019.04.106
Zhang, D., Hu, M., & Ji, Q. (2020). Financial markets under the global pandemic of COVID-19. Finance Research Letters, 36, 101528. https://doi.org/10.1016/j.frl.2020.101528
Zhao, L., Li, W., & Cai, X. (2016). Structure and dynamics of stock market in times of crisis. Physics Letters A, 380(5), 654–666. https://doi.org/10.1016/j.physleta.2015.11.015
Zhu, S., Kou, M., Lai, F., Feng, Q., & Du, G. (2021). The connectedness of the Coronavirus Disease pandemic in the world: A study based on complex network analysis. Frontiers in Physics, 8. https://doi.org/10.3389/fphy.2020.602075