THE VARIANCE RATIO TEST: AN ANALYSIS OF SIZE AND POWER BASED ON A CONTINUOUS-TIME ASYMPTOTIC FRAMEWORK
方差比检验:连续时间渐近框架下的尺寸与功效分析
We consider the statistical properties of the variance ratio statistic in the context of testing for market efficiency defined by uncorrelated returns. The statistic is then the ratio of the variance of K-period returns to the variance of one-period returns scaled by K. We use a continuous-time asymptotic framework whereby we let the sample size increase to infinity keeping the span of the data fixed. We also let the aggregation parameter K increase such that K/T → κ as T,…