Improving of Test Statistic for the Risk Ratio in a Correlated 2 x 2 Table with Structural Zero

บทคัดย่อ

Abstract

The purpose of this research was to develop test statistic for the risk ratio in a correlated 2 x 2 table with structural zero when sample size is small. We studied Wald test statistic, Logarithmic transformation test statistic, Fieller’s test statistic, Rao’s score test statistic and improving Wald test statistic. Also, we consider the performance of hypothesis testing for the risk ratio by power of the test and type I error rate close to the significant level. Simulation studies suggest improving Wald test statistic has type I error rate closest to significant level and powerful test when risk ratio value in alternative hypotheses are less.

Keywords: Power of tests, Test of hypothesis, Wald test