Because stock prices are not normally distributed, the power of nonparametric rank tests dominate parametric tests in event study analyses of abnormal returns on a single day. However, problems arise in the application of nonparametric tests to multiple day analyses of cumulative abnormal...

This paper proposes a novel standardized test for abnormal returns in long-horizon event studies that takes into account cross-sectional correlation, autocorrelation, and hetersoskedasticity of stock returns. Extensive simulation analyses demonstrate improved size and power of testing relative...

This study applies a rolling estimation window approach to adjust for time-varying risk parameters in asset pricing models to compute long-run abnormal returns after major corporate events. Abnormal returns are defined as realized returns minus predicted returns on each day in a five-year,...

This article examines the issue of cross-sectional correlation in event studies. When there is event-date clustering, we find that even relatively low cross-correlation among abnormal returns is serious in terms of over-rejecting the null hypothesis of zero average abnormal returns.We propose a...

This paper investigates the robustness of existing long-run event study methodologies using the Asia-Pacific security market data. In doing so, the study employs the buy-and-hold abnormal return approach and the calendar time portfolio method to measure the return anomalies. Since each of these...

Because of non-normality of stock returns nonparametric rank tests are gaining incremental popularity over parametric tests in financial economics event studies. In rank tests financial assets' multiple day cumulative abnormal returns (CARs) are replaced by cumulated ranks. This paper proposes...

Because of non-normality of stock returns nonparametric rank tests are gaining incremental popularity over parametric tests in event studies. In rank tests multiple day cumulative abnormal returns (CARs) are replaced by cumulated ranks. We propose modifications to the existing approach that...