The Effects of the Maastricht on Portfolio Diversification (Published)
Whether economic interdependence among countries is a contributing factor to co-integration and common stochastic trends in international stock markets is indiscernible due to conflicting results from prior empirical works. The purpose of this study is in two folds: Firstly to investigate whether the implementation of the Maastricht treaty has played any role in determining the long-run relationship between U.K stock market and other E.U and non-E.U stock markets and also to investigate the extent to which world stock markets have been correlated in the short-run over the study period and how such relationships would benefit investors in their portfolio diversification decisions. Data for this study was obtained from M.S.C.I indices and covered the period from 1985-2003. The methodologies used for this study are the correlation coefficient, the Vector Error Correction model and Vector Autoregressive model for the short-run relationship as well as the Johansen Co-integration approach for testing the long-run stochastic trend among the variables under consideration. The results for the short-run relationship among the variables indicates that in general, stock markets from the developed economies have become integrated in the short-run after the implementation of the Maastricht treaty compared to the pre-Maastricht treaty era. The results also show that the U.K stock market shows high correlation with the U.S stock market both before and after the implementation of the treaty and that correlation with other European Union economies, increased after the treaty. The co-integration results for the pre-Maastricht treaty period showed 2 co-integrations among the variables but there was no evidence of co-integration after the implementation of the treaty. However, when test was carried out for the whole study period, the results showed 1 co-integration among the sample country indices. The implication from the above results shows that diversification benefits for international investors wishing to invest into these developed markets especially in the short-run should expect reduced gains. However, long-term diversification benefits are possible as long as the correlations between these markets are low.
Keywords: Co-integration, European Union., Maastricht Treaty, Portfolio Diversification, Stock Market
Empirical Analysis of Effects of Inflation on Aggregate Stock Prices in Nigeria: 1980-2012 (Published)
This paper investigates empirically the effects of inflation on aggregate stock prices in Nigeria during the period of 1980-2012. Annual time series data on Stock Prices (ASP) and inflationary pressure measure were sourced from the Central Bank of Nigeria Statistical bulletin and Nigeria Stock Exchange Fact book. Employing the Engle-Granger and Johansen-Joselius method of co-integration in a Vector Error Correction Model (VECM) setting, in addition to Granger causality Test, Argumented Dickey Fuller Test (ADF) was employed. The empirical results shows that there exist a long run equilibrium negative and significantly relationship between inflation rate and aggregate stock prices, Broad money supply (M2) has a negative and significantly effects on aggregates stock prices, Narrow Money Supply (M1) shows a positive and significantly effects on aggregates stock prices while Average inflation rate show a positive and significantly relationship between aggregate stock prices. The results also show a strong relationship with an R2 of 0.886 representing 89.6% variations in the explanatory variables. However, the direction of causality between the money supply measures and aggregate stock prices is mixed. We recommend for the strengthening of monetary policy objective of price stability for the purpose of achieving efficiency in performance of the stock prices quoted in the Nigerian Stock Exchange (NSE).
Keywords: Aggregate Stock Prices, Co-integration, Inflation Rate, Unit Root Causality Tests