These study tips are designed to clarify key points and help you to avoid errors that students commonly make. Review the Tips for Success as you study each chapter and review them again after you have studied each chapter.
- This chapter builds very directly on Chapters 4 and 5. We do not recommend embarking on this chapter until you have a strong grasp of the key material in those chapters, especially hypothesis testing and the distribution of means.
- Notice that what you are doing on page 193 is basically the same as figuring Z scores. And, like when figuring Z scores, you can compare apples to oranges in the sense that you can compare results on different measures with different means and standard deviations.
- If you are all unsure about Type I and Type II errors, take some time now to review the Decisions Errors section in Chapter 4. As a brief reminder, you make a Type I error if the hypothesis-testing procedure leads you to decide that a study supports the research hypothesis when in reality the research hypothesis is false. You make a Type II error if the hypothesis-testing procedure leads you to decide that the results of a study are inconclusive when in reality the research hypothesis is true. Remember that these errors do not come about due to errors in figuring or poor decision making; they occur because in the hypothesis-testing process you are making probabilistic decisions about populations based on information in samples.
- When figuring power, it is very helpful to make a diagram of the two distributions (for an example, see Figure 6-6, p. 226).
