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  4. Analysis of the Nigerian stock market before and after the currency note changes using social network analysis

Analysis of the Nigerian stock market before and after the currency note changes using social network analysis

MMC.
2025;
Volume 12, Number 2
: pp. 650–660
https://doi.org/10.23939/mmc2025.02.650
Received: March 27, 2025
Revised: June 19, 2025
Accepted: June 21, 2025

Murtala A., Asrah N. M., Djauhari M. A.  Analysis of the Nigerian stock market before and after the currency note changes using social network analysis.  Mathematical Modeling and Computing. Vol. 12, No. 2, pp. 650–660 (2025)

Authors:
  1. A. Murtala
  2. N. M. Asrah
  3. M. A. Djauhari
1
Department of Mathematics and Statistics, Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia
2
Department of Mathematics and Statistics, Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia
3
KH Badruzzaman (STAI) University College of Islamic Religion, Garut, Indonesia

This paper examines the dependency of stocks in the Nigerian stock market from 2022 to 2023, focusing on the impact of currency note changes in government policy.  The study employs the forest of all minimum-spanning trees derived from the correlation matrix of the top 40 stocks across various sectors and four traditional centrality measures to identify the most influential stocks within the network.  The network analysis results reveal that the sectors dominating the market before the policy change differed from those dominating after the policy change.  Additionally, the analysis indicates shifts in dominance and dependency relationships among the stocks.  These findings provide valuable insights for policymakers and market participants, offering a clearer understanding of inter-sector stock relationships and facilitating the identification of stocks with positive or negative correlations.

network analysis
forest of all minimum spanning trees
centrality measures
stock market
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