Question

In today’s “wired” society, students believe they can multitask. Research suggests that 5% of individuals truly have the ability to multitask. Researchers are interested in finding out if students can multitask or if they perform worse while multitasking. In an introductory statistics class, students were randomly divided into two groups: texting group and cell phone off group. 92 students were required to send three text messages during the lecture and 92 students were required to turn off their cell phones. At the end of class, a quiz was administered based on information shared during class. The mean mark (in %) for the texting group was 52.18 with a standard deviation of 9.91. The mean mark (in %) for the cell phone off group was 68.76 with a standard deviation of 10.42.

1. a) Identify whether the sampling method used in this study is independent or dependent. Explain.

2. b) Estimate the mean difference in scores between the texting group and cell phone off group with

   90% confidence. Does the sample evidence suggest there is a difference in mean marks

   between the groups? If so, interpret the difference by identifying which group performs worse.

3. c) Conduct a hypothesis test to determine whether the data suggests students score worse in the texting group at the ? = 0.05 level of significance. Use the critical value method. (Show all six steps for hypothesis testing.)

Answer 1