Sequential Test for Correlation Coefficients

Abstract

Abstract A sequential test for correlation coefficients is presented. The method consists of reducing the test of a correlation coefficient to that of a variance ratio and making use of Helmert transformations of sequential observations. The resulting test is identified as the sequential probability ratio test regarding the parameter of the Cauchy distribution. The average sample number of the test is given and it is shown that the proposed sequential test yields an appreciable saving in the required average number of observations compared to the usual fixed sample size test.