Question 8.71

8.71 Effect of the sample size

Refer to the previous exercise. Similar results from a smaller number of students may not have the same statistical significance. Specifically, suppose that 124 of 136 men surveyed were employed and 106 of 122 women surveyed were employed. The sample proportions are essentially the same as in the earlier exercise.

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  1. Compute the statistic for these data, and report the -value. What do you conclude?
  2. Compare the results of this significance test with your results in Exercise 8.70. What do you observe about the effect of the sample size on the results of these significance tests?

8.71

(a) . The data show no significant difference between the proportions of male and female students employed during the summer. (b) The smaller sample sizes are not big enough to detect the practical difference we observed in the previous exercise.