Exercises
1. Test at a 5% significance level whether or not state and blood type are independent of each
other using the following sample data.
Type O Type A Type B Type AB
New York 50 40 35 10
California 125 100 120 30
2. Test at a 5% significance level whether or not car ownership and cell phone ownership are
independent of each other using the following sample data.
Owns Cell Phone Do Not Own Cell Phone
Owns Car 500 140
Does Not Own Car 125 80
Solutions
1. The p-value is .58. We fail to reject the null hypothesis and conclude that the two variables
may be independent of each other.
2. The p-value is less than .0001 so we reject the null hypothesis that the row and column
variables are independent of each other. Car ownership does influence cell phone ownership.
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