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Contingency Tables: SPSS: KEY
Before you boot up SPSS, obtain the following data file from my SPSS Data Page:
Howell.sav.
The data were collected from 88 school children in Vermont. Click here to see a
description of the variables.
Construct a contingency table to investigate the relationship between gender and
repeating a grade. Click Analyze, Descriptive Statistics, Crosstabs. Scoot Gender into the
Rows box and Repeat into the Columns box. Click OK.
GENDER * REPEAT Crosstabulation
Count
GENDER
Total






male
female
REPEAT
norepeat
repeated
45
10
31
2
76
12
Total
55
33
88
The marginal probability of repeating a grade is 12/88 = .136, ignoring gender.
The joint probability of being male and repeating a grade is 10/88 = .114.
The probability of being male OR repeating a grade is 57/88 = .647.
Among male students, the probability of repeating a grade is 10/55 = .182.
Among female students, the probability of repeating a grade is 2/33 = .061.
Copyright 2014, Karl L. Wuensch - All rights reserved.
2




Gender and repeating a grade are NOT INDEPENDENT, they are correlated.
Repeating a grade is more likely for male students than for female students.
The odds of repeating a grade are 10 to 45 for male students.
The odds of repeating a grade are 2 to 31 for female students.
10 / 45
 3.44 . For male students the odds of repeating a grade are
The odds ratio is
2 / 31
more than 3 times what they are for female students.
3
Now you do a crosstabulation between Gender and Socprob. Answer each of the
following questions.
ge nde r * socprob Crossta bul ation
Count
gender
Total
male
female
socprob
no_probs
problems
48
7
30
3
78
10
Total
55
33
88
 What is the marginal probability of having social problems?
10/88 = .114
 What is joint probability of being male and having social problems?
7/88 = .080
 What is the probability of being male OR having social problems?
58/88 = .659
 Among male students, what is the probability of having social problems?
7/55 = .127
 Among female students, what is the probability of having social problems?
3/33 = .091
 Are gender and having social problems independent or correlated? If correlated,
describe how they are correlated.
Boys more likely than girls to have social problems.
 Among male students, what are the odds of having social problems?
7/48
 Among female students, what are the odds of having social problems?
3/30
 What is the male to female odds ratio for having social problems?
1.458
4
Now you do a crosstabulation between Gender and DropOut. Answer each of the
following questions.
ge nde r * dropout Crossta bul ation
Count
gender
Total
male
female
dropout
graduated
dropped
48
7
30
3
78
10
Total
55
33
88

What is the marginal probability of dropping out? 10/88 = .114

What is joint probability of being male and dropping out? 7/88 = .080

What is the probability of being male OR having dropping out? 58/88 = .659

Among male students, what is the probability of dropping out? 7/55 = .127

Among female students, what is the probability of dropping out? 3/33 = .091
 Are gender and dropping out independent or correlated? If correlated, describe how
they are correlated. Boys are more likely than girls to drop out.

Among male students, what are the odds of dropping out? 7/48

Among female students, what are the odds of dropping out? 3/30

What is the male to female odds ratio for dropping out? 1.458
5
Now you do a crosstabulation between Repeating a Grade and Social Problems.
Answer each of the following questions.
re pea t * socprob Crossta bula tion
Count
repeat
Total
norepeat
repeat ed
socprob
no_probs
problems
69
7
9
3
78
10
Total
76
12
88

What is the marginal probability of having social problems? 10/88 = .114

What is joint probability of repeating a grade and having social problems? 3/88 = .034

What is the probability of repeating a grade OR having social problems? 19/88 = .216
 Among those who have repeated a grade, what is the probability of having social
problems? 3/12 = .25
 Among those who have not repeated a grade, what is the probability of having social
problems? 7/76 = .092
 Are repeating a grade and having social problems independent or correlated? If
correlated, describe how they are correlated. Those who have repeated a grade are more
likely to have social problems than those who have not repeated a grade.
 Among those who have repeated a grade, what are the odds of having social
problems? 3/9
 Among those who have not repeated a grade, what are the odds of having social
problems? 7/69

What is the repeated to not repeated odds ratio for having social problems? 3.286
6
Now you do a crosstabulation between Repeating a Grade and Dropping Out. Answer
each of the following questions.
re pea t * dropout Crosstabula tion
Count
repeat
Total
norepeat
repeat ed
dropout
graduated
dropped
72
4
6
6
78
10
Total
76
12
88
 What is the marginal probability of dropping out?
10/88 = .114
 What is joint probability of repeating a grade and dropping out?
6/88 = .068
 What is the probability of repeating a grade OR dropping out?
16/88 = .182
Among those who have repeated a grade, what is the probability of dropping out?
6/12 = .50
 Among those who have not repeated a grade, what is the probability of dropping out?
4/76 = .053
 Are repeating a grade and dropping out independent or correlated? If correlated,
describe how they are correlated.
Those who have repeated a grade are more likely to drop out than those who have not
repeated a grade.
 Among those who have repeated a grade, what are the odds of dropping out?
6/6
Among those who have not repeated a grade, what are the odds of dropping out?
4/72
 What is the repeated to not repeated odds ratio for dropping out?
18 – the odds of dropping out are 18 times higher among those who have repeated a
grade compared to those who have not completed a grade. (6/6)/(4/72) = 72/4 = 18.
7
Now you do a crosstabulation between having Social Problems and Dropping Out.
Answer each of the following questions.
socprob * dropout Crosstabulati on
Count
socprob
Total
no_probs
problems
dropout
graduated
dropped
73
5
5
5
78
10
Total
78
10
88
 What is the marginal probability of dropping out?
10/88 = .114
 What is joint probability of having social problems and dropping out?
5/88 = .057
 What is the probability of having social problems OR dropping out?
15/88 = .170
 Among those who have had social problems, what is the probability of dropping out?
5/10 = .50
 Among those who have not had social problems, what is the probability of dropping
out?
5/78 = .064
 Are having social problems and dropping out independent or correlated? If correlated,
describe how they are correlated.
Those who have had social problems are more likely to drop out than are those who have
not had social problems.
 Among those who have had social problems, what are the odds of dropping out?
5/5
 Among those who have not had social problems, what are the odds of dropping out?
5/73
 What is the had social probs to not had social probs odds ratio for dropping out?
14.6
Return to my SPSS Lessons page
More Lessons on the Binomial and Chi-Square Distributions
Contingency Table Analysis with SAS
8
Letters From Former Students -- some continue to use my online lessons when they go on to
doctoral programs.
Copyright 2014, Karl L. Wuensch - All rights reserved.