This article investigates the finite-sample performance of a modified Box-Pierce Q statistic (Q*) for testing that financial time series are uncorrelated without assuming statistical independence. The finite-sample rejection probabilities of the Q* test under the null and its power are examined...

The authors test for the presence of long memory in daily stock returns and their squares using a robust semiparametric procedure of I. Lobato and P. M. Robinson (1997). Spurious results can be produced by nonstationarity and aggregation. The authors address these problems by analyzing...