Summary
In this chapter, we introduced the concept of a hypothesis test. We started with a basic outline of a hypothesis test with the four key steps:
- State the hypothesis
- Perform the test
- Determine whether to reject or fail to reject the null hypothesis
- Draw a statistical conclusion with a scope of inference
Then we talked about potential errors that can occur and false positives and false negatives and defined the expected error rate (alpha) of a test and the power (beta) of a test.
We also discussed the statistical procedure called the z-test. This is a type of hypothesis test using sample data assumed to be normally distributed. The z-score and z-statistic were also introduced in the section on different types of z-tests, such as one-sample or two-sample z-tests for means or proportions.
Finally, we discussed the concept and motivation behind the power analysis, which can be used to identify the probability of incorrectly rejecting the null hypothesis...