## Setting Up Hypotheses

This section discusses the logic behind hypothesis testing using concrete examples and explains how to set up null and alternative hypothesis. It explains what Type I and II errors are and how they can occur. Finally, it introduces one-tailed and two-tailed tests and explains which one you should use for testing purposes.

### Type I and Type II Errors

#### Questions

Question 1 out of 5.

It has been shown many times that on a certain memory test, recognition is substantially better than recall. However, the probability value for the data from your sample was.12, so you were unable to reject the null hypothesis that recall and recognition produce the same results. What type of error did you make?

• Type I
• Type II

Question 2 out of 5.

In the population, there is no difference between men and women on a certain test. However, you found a difference in your sample. The probability value for the data was.03, so you rejected the null hypothesis. What type of error did you make?

• Type I
• Type II

Question 3 out of 5.

As the alpha level gets lower, which error rate also gets lower?

• Type I
• Type II

Question 4 out of 5.

Beta is the probability of which kind of error?

• Type I
• Type II

Question 5 out of 5.

If the null hypothesis is false, you cannot make which kind of error?

• Type I
• Type II