Provides answers to commonly asked questions about COBRA. Health Benefits Under the Consolidated Omnibus Budget Reconciliation Act (COBRA) (PDF) Provides a detailed overview of the major provisions of COBRA.
In the two-sample pooled t-test the pooled variance is computed by averaging the two individual sample variances. The assumptions for the two-sample pooled t-test for the difference in two means are that there are random samples from two independent normal populations with common but unknown variance.
T-test. The ttest command performs t-tests for one sample, two samples and paired observations. The single-sample t-test compares the mean of the sample to a given number (which you supply). The independent samples t-test compares the difference in the means from the two groups to a given value (usually 0).In other words, it tests whether the difference in the means is 0.he single sample t-test tests the null hypothesis that the population mean is equal to the given number specified using the option write == . For this example, we will compare the mean of the variable write. In this example, the t-statistic is 4.1403 with 199 degrees of freedom.