Transcript Notes on Test of Indepencence

Test of Independence
Section 12.2 (cont)
Independent
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Knowledge of one value does not provide
information about another.
Very similar to Test of
Homogeneity
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Same test statistic
Same way to figure the expected value
Same way to find the degrees of freedom
Same way of putting it in the matrices and
using the calculator.
Differences
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 H o : the 2 variables are independent
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 H A : the 2 variables are not independent
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State in context of the problem
Assumptions
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Random samples
Cells 5
A sociologist wishes to see whether the number of years of
college a person has completed is related to his or her place
of residence. A random sample of 70 people is selected and
classified as shown. Using a 5% significance level, can the
sociologist conclude that the years of college education are
dependent on the person’s location?
No College
4 yr deg
Advanced
Urban
15
12
8
Suburban
8
15
9
Rural
6
8
7
A researcher wishes to determine whether there is a
relationship between the gender of an individual and
the amount of alcohol consumed. Use α = 0.01
Low
Moderate
High
Male
10
9
8
Female
13
16
12
Survey Questions
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Each Group is to make a survey question that
will generate data for each type of Chi-square
Test.
Homework
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Page 659 (20, 24, 25, 30, 32)
Test for Homogeneity are mixed in with test
of independence!