Research Methods And Statistics II

Research Methods and Statistics II
Final exam problems (take-home exam)
A random sample of students were asked to take a memory test before and after being spun really fast in a sit-and-spin. They were then asked to report whether or not they felt dizzy. Please note that one of the problems below will use a Chi Square to solve. In general, a Chi Square should not be used when your expected value in any cell is less than 5, but ignore this restriction for the purpose of this exam.
Problems:
1. Following the four steps of hypothesis testing, evaluate whether there is a difference between how someone scores on the pretest vs. the posttest (include males and females in the same sample).
2. Following the four steps of hypothesis testing, evaluate whether there is a difference between males and females on whether or not they get dizzy.
3. Following the four steps of hypothesis testing, evaluate whether gender (males vs. females) and dizziness (yes vs. no) affect posttest scores. Use the following descriptive statistics and partially filled summary table to complete your computations and write up.
Descriptive Statistics
Dependent Variable:Posttest
Gender
Dizzy
Mean
Std. Deviation
N
Male
No
34.2500
5.05800
4
Yes
28.5000
2.12132
2
Total
32.3333
5.00666
6
Female
No
27.6667
4.93288
3
Yes
23.3333
7.09460
3
Total
25.5000
5.95819
6
Total
No
31.4286
5.76938
7
Yes
25.4000
5.85662
5
Total
28.9167
6.34548
12
Summary Table:
Sum of Squares
df
Mean Square
F
Gender
97.456
1
Dizzy
71.770
1
Gender*Dizzy
1.417
1
Error
230.583
8
For example:
What is the mean of 5, 11, 2?
Subject
Gender
Pretest score
Posttest score
Dizzy
1
Male
34
27
Yes
2
Male
46
30
Yes
3
Male
31
30
No
4
Male
28
30
No
5
Male
39
37
No
6
Male
37
40
No
7
Female
42
31
Yes
8
Female
38
22
No
9
Female
22
17
Yes
10
Female
33
30
No
11
Female
34
22
Yes
12
Female
41
31
No
Sheet1
Subject Gender Pretest score Posttest score Dizzy
1 Male 34 27 Yes
2 Male 46 30 Yes
3 Male 31 30 No
4 Male 28 30 No
5 Male 39 37 No
6 Male 37 40 No
7 Female 42 31 Yes
8 Female 38 22 No
9 Female 22 17 Yes
10 Female 33 30 No
11 Female 34 22 Yes
12 Female 41 31 No
6
3
18
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