The t test for two independent samples - Two-tailed example

The group of 30 victims scored an average of 21.5 with a sample standard deviation of 10 on the anxiety scale. The group of 27 bully-victims scored an average of 25.8 with a sample standard deviation of 9 on the same scale. You do not have any presupposed assumptions about whether victims or bully-victims will be more anxious, so you formulate the null and alternative hypotheses as:

1. The degrees of freedom is: ______
2. The critical t-scores that form the boundaries of the rejection region for = 0.01 are : ______
3. The pooled variance is s2/p =______. The standard error is s(M1 - M2) = ______
4. The t statistic is: ______
5. The t statistic______ in the rejection region. Therefore, the null hypothesis is______. You conclude that victims have a different mean anxiety score than bully-victims. Thus, it can be said that these two means are______ different from one another.