Question

4. Research shows that similarity in attitudes, beliefs, and interests plays an important role in interpersonal attraction. Thus in theory, one’s attitude should be similar to that of his/her relationship partner. Suppose a researcher developed a questionnaire that measures how liberal or conservative one’s attitudes are. Low scores indicate that the person has liberal attitudes, whereas high scores indicate conservatism. The following hypothetical data are scores for married couples.

Couple	x : partner 1	y : partner 2
A	11	14
B	6	7
C	16	15
D	4	7
E	1	3
F	10	9
G	5	9
H	3	8

Th researcher hypothesizes that partners’ attitudes are significantly related to each other.

5. For the following data, x1 represents a rating of a client’s satisfaction after the first therapy session (on a scale of 1-10). x2 represents a rating of a client’s self-reported happiness before the first therapy session (on a scale of 1-12). y represents the number of sessions attended by that client after three months.

Client	x1 : satisfaction	x2 : happiness	y : # sessions
A	7	12	16
B	5	6	2
C	6	6	1
D	3	5	2
E	4	8	9
F	10	6	12
G	3	3	4
H	10	3	11
I	6	7	8

A researcher hypothesizes that greater satisfaction after the first session, and less happiness before the first session, will each lead one to attend more sessions.

6. Suppose a survey of Psych 320 students finds the following data for the students' favorite basketball team:

​Lakers​​Clippers​​Warriors​​Kings

​   55​​​   27​​​   13​​​   1

Do the data indicate a significant preference among the four basketball teams?

7. Shrauger (1972) conducted an experiment that compared the effect of an audience on the performance of participants with high and low self-esteem. Hypothetical data from this experiment are as follows. The data represents the number of errors made by each participant (6 participants in each condition):

		Alone	With audience
Self-esteem	High	3, 6, 2, 2, 4, 7	9, 4, 5, 8, 4, 6
	Low	7, 7, 2, 6, 8, 6	10, 14, 11, 15, 11, 11

Is there 1) a main effect of self-esteem, 2) a main effect of alone/audience, and 3) an interaction between the two?

Answer 1

Note : Allowed to solve one question per post.

Two-way ANOVA in excel

Step 1 : Put the data in excel as shown.

Step 2 : Go to DATA -> Data analysis -> Two-way ANOVA with replication

Step 3 : Input the values are shown

Step 4 : The output will be generated as follows.

Hypothesis 1

Ho : The mean number of error for the two self-esteem levels are equal
H0 : The mean number of error for the two self-esteem levels are not equal

From the anova output we see that the pvalue corresponding to self-esteem is 0.0013, which is less than 0.05, hence we reject the null hypothesis and conclude that the mean number of error for the two self-esteem levels are not equal

Hypothesis 2

Ho : The mean number of error for the two audience levels are equal
H0 : The mean number of error for the two audience levels are not equal

From the anova output we see that the pvalue corresponding to the audience is 0.0013, which is less than 0.05, hence we reject the null hypothesis and conclude that the mean number of error for the two audience levels are not equal

Hypothesis 3

HO: There is no interaction between self-esteem level and audience level
H1: There is the interaction between self-esteem level and audience level

From the anova output we see that the pvalue corresponding to interaction is 0.02, which is less than 0.05, hence we reject the null hypothesis and conclude that there is the interaction between self-esteem level and audience level