31. Spam, Spam, Spam. Continue your work from the previous exercise. The following contingency table shows the actual percentages in the graph above based on samples of size 100 for each of work email and personal email. Test whether the proportions who report “a lot of spam” are the same for work email and personal email, using level of significance . Does your conclusion agree with your conjecture in the previous exercise?
| None | Some | A lot | |
|---|---|---|---|
| Work email | 53% | 36% | 11% |
| Personal email | 22% | 48% | 30% |
11.2.31
. : Not all the proportions in are equal. Reject if -value . Since none of the expected frequencies is less than 1 and none of the expected frequencies is less than 5, the conditions for performing the test for homogeneity of proportions are met. . -value ≈ 0. Since -value , we reject . There is evidence that the population proportions who report “a lot of spam” are not the same for work email and personal email. Yes.