How Is Mean Difference Calculated? The standardized mean difference (d) To calculate the standardized mean difference between two groups, subtract the mean of one group from the other (M1 – M2) and divide the result by the standard deviation (SD) of the population from which the groups were sampled. What is the mean difference value?
What Does Equal Variance Mean In T Test? What does equal variance mean in t test? Two-sample T-Test with equal variance can be applied when (1) the samples are normally distributed, (2) the standard deviation of both populations are unknown and assumed to be equal, and (3) the sample is sufficiently large (over 30). What
When Can You Assume Population Variances Are Equal? If sample sizes are equal, the pooled and unpooled standard errors are equal. If sample standard deviations are similar, assumption of equal population variance may be reasonable and the pooled procedure could be used. How do you know if population variances are equal? If the variances are