This study examines the impact of FTSE 100 index revisions on the informational efficiency of the underlying stocks. Our study spans the 1986–2009 period. We estimate the speed of price adjustment and price inefficiency from the partial adjustment with noise model of Amihud and Mendelson (1987). We report a significant improvement (no change) in the informational efficiency of the stocks added to (deleted from) the FTSE 100 index. The asymmetric effect of additions and deletions on informational efficiency can be attributed, at least partly, to certain aspects of liquidity and other fundamental characteristics, which improve following additions but do not diminish after deletions. Cross-sectional analysis also indicates that stocks with low pre-addition market quality benefit more from joining the index.

This study attempts to measure the effects on the share price of companies entering and exiting four FTSE/JSE indices; the J200, J210, J213 and J260. While results showed only weak statistical significance, systematic patterns were observed during the event window. Share prices of companies entering and exiting value weighted indices responded consistently with the investor awareness hypothesis. Share prices of companies entering and exiting indices weighted by fundamental factors responded consistently with the information hypothesis. The cumulative average abnormal returns (CAARs) were permanent and did not reverse within the first 200 days after the index change for all indices. Abnormal returns were calculated by using the market model and a one factor CAPM model. The market model was a superior benchmark in this study. This study found that the CAARs for index changes became positive only after the date of the index change. This implies that either the effect of passive index funds on the JSE is not significant, or that passive funds are allowed to incur tracking errors in order to trade strategically to secure the best price for a reconstituted portfolio. This conclusion is supported by the fact that there was no observable change in the index premium over time. The findings of this study may indicate market inefficiency, which means that arbitrage opportunities may exist around index changes. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted

No / We study the price and liquidity effects following the FTSE 100 index revisions. We employ the standard GARCH(1,1) model to allow the residual variance of the single index model (SIM) to vary systematically over time and use a Kalman filter approach to model SIM coefficients as a random walk process. We show that the observed price effect depends on the abnormal return estimation methods. Specifically, the OLS-based abnormal returns indicate that the price effect associated with the index revision is temporary, whereas both SIM with random coefficients and GARCH(1,1) model suggest that both additions and deletions experience permanent price change. Added (removed) stocks exhibit permanent (temporary) change in trading volume and bid-ask spread. The analysis of the spread components suggests that the permanent change associated with additions is a result of non-information-related liquidity. We interpret the permanent price effect of additions and deletions combined with the permanent (temporary) shift in liquidity of added (removed) stocks as evidence in favour of the imperfect substitution hypothesis with some non-information-related liquidity effects in the case of additions.

No / We examine short- and the long-term price effect associated with the FTSE 100 index revisions. We control for both heteroskedastic nature of the residual and the change, between the estimation and the test period, in the beta coefficient of the standard market model. Our findings reveal no relationship between the long-term price reversals and the change in the discount rate, as approximated by the beta coefficient of the market model. Overall, we provide strong evidence in favour of the price pressure hypothesis, where the price increase (decrease) gradually starting before the announcement an inclusion (exclusion) and reverses completely in less than two weeks after the index revision date.

This thesis examines the impact of FTSE 100 index revisions on the various aspects of stock market quality and the cost of equity capital. Our study spans over the period 1986-2009. Our analyses indicate that the index membership enhances all aspects of liquidity, including trading continuity, trading cost and price impact. We also show that the liquidity premium and the cost of equity capital decrease significantly after additions, but do not exhibit any significant change following deletions. The finding that investment opportunities increases after additions, but do not decline following deletions suggests that the benefits of joining an index are likely to be permanent. This evidence is consistent with the investor awareness hypothesis view of Chen et al. (2004, 2006), which suggests that investors' awareness improve when a stock becomes a member of an index, but do not diminish after it is removal from the index. Finally, we report significant changes in the comovement of stock returns with the FTSE 100 index around the revision events. These changes are driven mainly by noise-related factors and partly by fundamental-related factors.

This thesis examines the impact of FTSE 100 index revisions on the various aspects of stock market quality and the cost of equity capital. Our study spans over the period 1986¿2009. Our analyses indicate that the index membership enhances all aspects of liquidity, including trading continuity, trading cost and price impact. We also show that the liquidity premium and the cost of equity capital decrease significantly after additions, but do not exhibit any significant change following deletions. The finding that investment opportunities increases after additions, but do not decline following deletions suggests that the benefits of joining an index are likely to be permanent. This evidence is consistent with the investor awareness hypothesis view of Chen et al. (2004, 2006), which suggests that investors¿ awareness improve when a stock becomes a member of an index, but do not diminish after it is removal from the index. Finally, we report significant changes in the comovement of stock returns with the FTSE 100 index around the revision events. These changes are driven mainly by noise-related factors and partly by fundamental-related factors. / International Fellows Program, USA, (IFP) and American-Mideast-Educational and Training Services, Inc. (AMIDEAST).