PSYC 355 - An entrepreneur claims that he has developed a program that can increase the IQ of adolescent students

The following research questions can be answered using 1 of the 5 tests you have learned so far:
single-sample t-test, paired-samples t-test, independent-samples t-test, one-way ANOVA, or twoway ANOVA. Use the information in the tables to construct your SPSS data file, just as you have
been doing in Part 2 of each homework assignment. There is only 1 correct choice of analysis
for each question. The assessment is open-book/open-notes.

For each problem involving a test of significance, your answer must include: A) the output and
an appropriate graph from SPSS; B) a statistical statement (i.e., t(19) = 1.79, p = .049); and C) a
sentence summarizing the results (i.e., There was a significant difference between the two
groups on the variable or There was no significant difference).

For ANOVA problems: Report statistical findings and make statements for all main effects and
interaction effects. Use the Fisher LSD test for any analyses requiring post hoc tests.
Submit this assignment by 11:59 p.m. (ET) on Monday of Module/Week 5.

1. An entrepreneur claims that he has developed a program that can increase the IQ of
adolescent students. To test this claim, a psychologist administers the WISC (an IQ score for
children) to a group of students before and after completing the training program. Analyze
the data to test the entrepreneurs claim. (16 pts)

Student IQ
before
1
103
2
85
3
94
4
106
5
74
6
98
7
83
8
93
9
103
10
96
11
109
12
115
13
86
14
122
15
112
16
126
17
118
18
72

IQ after
99
89
90
108
74
99
80
99
107
93
111
117
83
122
120
131
116
74

Page 1 of 3

PSYC 355

2. The staff at a local psychiatric facility wants to determine whether implementing a No
Smoking rule significantly decreases the length of stay of inpatients. In order to test this
claim, they compared the length of stay of patients admitted before a No Smoking rule was
implemented to another group of patients admitted after the No Smoking rule was
implemented. Evaluate the claim that the average length of stay was significantly shorter for
the group admitted after the facility implemented the rule. (16 pts)
Smoking Allowed
8
7
5
15
2
12
5
8
8
4
6
13
4
10
14
8

No Smoking
5
4
10
8
7
4
8
5
2
2
3
4
2
6
4
7

3. Depressed patients are randomly assigned to 1 of 3 therapists. At the end of 3 months, each
patient completes a standardized test of depression (higher scores indicate higher level of
depression). The patients scores are shown below. Analyze the data to determine how
effective these 3 therapists are at treating depression (assume that before the treatment, all 3
groups of patients had the same average depression score). (16 pts)
Therapist
1
35
37
35
37
36
33
39

Therapist 2 Therapist 3
36
37
37
31
39
35
32

29
32
25
28
33
30
32

Page 2 of 3

PSYC 355

4. In light of all the weight loss misinformation and fad diets, a medical researcher determines
to evaluate several of them. She randomly assigns volunteers (identified as clinically obese)
to 1 of 4 diets. She is a firm believer in the benefits of exercise, so she also assigns them to
either the exercise or no exercise group. After 3 months, she compares the pounds lost for
each condition. Was there a significant effect of the diets and exercise on weight loss? (16
pts)
Low Carb
Exercise

No
Exercise

26
28
30
25
20
15
20
18

South
Beach
28
22
18

18
12
15
15

Adkins
25
21
24
29
17
19
28
25
21

Weight
Watchers
28
28
30
25
26
34
25
30
28

5. Infants exposed to cocaine in their mothers womb are thought to be at high risk for major
birth defects. Thirteen infants born to mothers who are addicted to cocaine are administered
the Brazelton Neonatal Assessment 1 day after birth. For these babies, their scores were as
follows:
Brazelton Scores
6.25
4.50
8.50
5.50
3.00
7.90
7.50
5.30
6.80
7.50
5.25
7.45
6.80
For the general population, babies normally score an 8.5. Is this group of babies significantly
lower than normal? (16 pts)