- 30 Is There A Difference Between Reading Or Listening When It Comes To Retaining Information 20 Randomly Selected Peop 1 (73.14 KiB) Viewed 83 times
30. Is there a difference between reading or listening when it comes to retaining information? 20 randomly selected people are broken into two groups. The first group (group A, consisting of 8 people) spend a week reading factsheets about US history; the second group (group B, 12 people) listen to the same factsheets being read on an audio book. At the end of a week all 20 people take a standardized test on which the results are assumed to be normally distributed. The mean for group A was 75 with sample variance 16, and for group B was 80 with sample variance 25. (a) Assuming that the actual variances for the two types of groups are equal, use the data to compute S, the pooled estimator for the common variance. (b) Test at 5% significance the null hypothesis that the there is no difference in the mean score between readers and listeners, against the alternative that there is a difference.