To calculate the statistical power for a given Type I error α, we first use equation (4) to find the critical value λ 1−α and then use equation (5) to calculate ...

Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

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A maximum test in which the test statistic is the more extreme of the Brown-Forsythe and O'Brien's test statistics is developed. Estimated Type I error rates and ...

A t-test for population means compares the means between two populations. It is appropriate when the population standard deviations are unknown. This applet allows users to change the distributions of ...