Table : TABLE 7-2. The Three Assumptions for Hypothesis Testing We must be aware of the assumptions for the hypothesis test that we choose, and we must be cautious in choosing to proceed with a hypothesis test when the data may not meet all of the assumptions. Note that in addition to these three assumptions, for many hypothesis tests, including the z test, the independent variable must be nominal.
The Three Assumptions
Breaking the Assumptions
1. Dependent variable is on a scale measure.
Usually OK if the data are not clearly nominal or ordinal.
2. Participants are randomly selected.
OK if we are cautious about generalizing.
3. Population distribution is approximately normal.