In Example 3, you the alternative hypothesis leads you to reject the null hypothesis for either large or small values of xbar. This is a two tail test. There are two critical z-values, -1.96 and +1.96 ...

For another explanation of type 1 and type 2 errors, see this webpage. There are two ways of conducting any hypothesis test, namely one tailed and two tailed. In a one tailed test, we only look for a ...

Define a test statistic, level of significance, and the rejection region for a hypothesis test. Give the form of a rejection ... of Module 1 to composite hypotheses for both one and two-tailed tests.