Question

A child psychologist treated four children who were afraid of snakes with a behavioral modification procedure called systematic desensitization. In this procedure, children were slowly introduced to a snake over four treatment sessions. Children rated how fearful they were of the snake before the first session (baseline) and following each treatment session. Higher ratings indicated greater fear. Complete the F table for this within-subjects design and make a decision to retain or reject the null hypothesis.

Answer 1

As no data is provided, we will just provide the outline of the hypothesis and condition of rejection.

Let ri= rating of fear for ith^​ treatment session.

Hypothesis :

H0 : r1 =r2 = r3=r4 vs vs H1 : atleast one inequality of ri

Testing : we would test if the mean rating significantly varies or not. If, standard deciation is not known, we will use one sample t test else we will use one sample z test.

And reject the null hypothesis if the p-value > 0.05 where level of significance alpha=0.05