Factors Determining the Power of a Statistical Test for the Difference between Means and Proportions

One of the most essential issues in research problems design is statistical power of a test is. The problem motivating this topic is to identify the factors and relationships among the components of power analysis for a study. In this paper, we presented testing procedures of hypothesis for means and proportions in different sample situations. Hypothesis testing requires several stages, including specifying the null and alternative or research hypothesis, selecting and computing an appropriate test statistic, setting up a decision rule to reach a conclusion. Some related concepts such as sample size and confidence intervals were demonstrated, and illustrations on theoretical data would be carried. Results and conclusions on the basis of the discussions reflected the relationship among power analysis components and factors that influence the statistical power of a test would be shown.