Apps in this category may contain mild or occasional cartoon, fantasy or real-life violence, as well as occasional or mild adult, sexually suggestive or horrifying content and may not be suitable for children under 9 years of age.

12+

Apps in this category may contain occasional mild indecent language, frequent or intense cartoon or real-life violence, minor or occasional adult or sexually suggestive material, and simulated gambling, and may be for children under 12 years of age.

17+

You must be at least 17 years old to access this App.

Apps in this category may contain frequent and intense offensive language; Frequent and intense cartoon, fantasy or realistic violence: frequent and intense adult, scary and sexually suggestive subjects: as well as sexual content, nudity, tobacco, alcohol and drugs, may not be suitable for children under 17 years of age.

Quick Mean Difference 螢幕截圖

iPhone

About Quick Mean Difference

The mean difference is a measure of statistical dispersion between means of two independent samples.

This app tests the hypothesis that the means, μ, of two samples are equal at some level of probablility, p. The relevant statistic is the Student's t-test for the appropriate probability and degrees of freedom, df.

The critical value of the t-test for 5% probability at 30 degrees of freedom is shown as t(0.05, 30).  There are three assumptions imbedded in this test. First, the samples must be randomly generated. Second, the samples must be independently sampled meaning that the inclusion of one subject does not influence the probability of selecting any other member of the population. Third, the population variances, or standard deviations as input into this app, of the two samples, A and B, are presumed to be equal.