We propose sequential methods for obtaining approximate confidence limits and optimal sample sizes for the risk ratio (RR) of two independent binomial variates and a measure of reduction (MOR). The procedure is developed based on a modified maximum likelihood estimator (MLE) for the ratio. First-order asymptotic expansions are obtained for large-sample properties of the proposed procedure and we investigate its
finite sample behavior through numerical studies.
More information about Hokwon Cho may be found at https://faculty.unlv.edu/cho/