The data from problem 15 show no significant difference between the opinions for city residents and those who live in the suburbs. To construct the following data, we simply doubled the sample size from problem 15 so that all of the individual frequencies are twice as big. Notice that the sample proportions have not changed.

a. Test for a significant difference between the city distribution and the suburb distribution using α = .05. How does the decision compare with the decision in problem 14? You should find that a larger sample increases the likelihood of a significant result.
b. Compute the phi-coefficient for these data and compare it with the result from problem 15. You should find that the sample size has no effect on the strength of the relationship.

Opinion Oppose Favor 70 30 100 City Suburb 110 90 200 180 120