Abstract
In Taguchi method, several SN ratios are utilized in order to evaluate the performance of system. In this paper, we discuss binary input-output systems. In this situation, we usually have a 2×2 contingency table of frequency. In section 24.2 of Taguchi (1977), standardized SN ratios are used as measurement of efficiency in binary input-output systems. By contrast, in section 24.4, author discusses the problem of binary input-output systems observed continuous values and compares efficiency of two kinds of systems by using standardized SN ratios. In this paper, we propose statistical tests of the equality of performances by assuming that percentages of response follow the beta distribution. The power of proposed test is shown to be higher than that of two-sample location test. In addition, we discuss the number of repetitions of this experiment if values of contingency table are independent each other.
