If the variances are equal, the ratio of the variances will equal 1. For example, if you had two data sets with a sample 1 (variance of 10) and a sample 2 (variance of 10), the ratio would be 10/10 = 1. You always test that the population variances are equal when running an F Test. In other words, you always assume that the variances are equal 2. Conduct Welch’s t-test using the Analysis ToolPak. Navigate to the Data tab along the top ribbon. Then, under the Analysis group, click the icon for the Analysis ToolPak. In the box that pops up, click t-Test: Two Sample Assuming Unequal Variances, then click OK. Lastly, fill in the values below and then click OK: Step 2: Determine Equal or Unequal Variance. Next, we can calculate the ratio of the sample variances: Here are the formulas we typed into each cell: Cell E1: =VAR.S (A2:A21) Cell E2: =VAR.S (B2:B21) Cell E3: =E1/E2. We can see that the ratio of the larger sample variance to the smaller sample variance is 4.533755. A general rule of thumb for equal variances is to compare the smallest and largest sample standard deviations. This is much like the rule of thumb for equal variances for the test for independent means. If the ratio of these two sample standard deviations falls within 0.5 to 2, then it may be that the assumption is not violated. Homogeneity of variance-covariance matrices for e.g. MANOVA is tested with the Box’s M test which should be non-significant (Box’s M tests the statistical hypothesis that the variance-covariance matrices are equal). In fact, you can first check the univariate homogeneity of variance with Levene’s test for each individual dependent 1. I want to calculate the p-value between subgroups of my samples. For that, I am using the T.TEST function of Excel. But I do not understand the last parameter, type: Paired. Two-sample equal variance (homoscedastic) Two-sample unequal variance (heteroscedastic) In my case, I cannot use paired (not the same size). treatment variance to the smallest does not exceed 3 (some people say 4), then the inference procedures for the equal variance model are still valid. (However, a larger ratio might also occur by chance even when model assumptions are correct.) • With unequal sample sizes, departures from equal variance can have different Perhaps surprisingly, Levene’s test is technically an ANOVA as we'll explain here. We therefore report it like just a basic ANOVA too. So we'll write something like “Levene’s test showed that the variances for body fat percentage in week 20 were not equal, F(2,77) = 4.58, p = .013.”. 9Qt2.