CHAPTER 10

Use 2 decimals for all answers and show your work

A researcher is interested in evaluating two different treatments developed to treat depression. Test her hypothesis that the treatments lead to different results. Her data are below (a higher value indicates higher depression). Test with a = .01 YOU NEED TO CALCULATE THE MEANS AND THE STANDARD DEVIATIONS FOR YOUR DATA. Relaxation Meditation

24 32 22 32 31 27 27 23 23 38 34 34 28 23

Formulate the hypotheses.

Determine the critical value(s).

Calculate the test statistic.

Calculate and evaluate Cohen's d and r2.

What decision can you make and what does it indicate?

What type of error could you be making and what would that mean?

Report your results with an APA-style phrase.

In a study of jury behavior, two samples of participants were provided details about a trial in which the defendant was obviously guilty. Although group 2 received the same details as group 1, the second group was also told that some evidence had been withheld from the jury by the judge. Later, the participants were asked to recommend a jail sentence. The length of term suggested by each participant is presented here. Is there a significant difference between the two groups in their responses? Test with a = .01. For Group 1: M = 3, SS = 16, n = 10 For Group 2: M = 6, SS = 24, n = 10

Formulate the hypotheses.

Determine the critical value(s).

Calculate the test statistic.

Calculate and evaluate Cohen's d and r2.

What decision can you make and what does it indicate?

What type of error could you be making and what would that mean?