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.
Instructor: Orin Davis. T-tests are used to compare two means to assess whether they are from the same population. T-tests presume that both groups are normally distributed and have relatively equal variances. The t-statistic is distributed on a curve that is based on the number of degrees of freedom (df).