Please answer all questions.
19 - Section 4.5 Making Connections Question 9 of 9 View Policies Current Attempt in Progress Effect of Sleep and Caffeine on Memory A study is conducted in which a random sample of 24 adults are divided equally into two groups and given a list of 24 words to memorize. During a break, one group takes a 90 minute nap while another group is given a caffeine pill. The response variable of interest is the number of words participants are able to recall following the break. We are testing to see if there is a difference in the average number of words a person can recall depending on whether the person slept or ingested caffeine. The data are shown in Table 1 below. Sleep 14 18 11 13 18 17 21 9 16 17 14 15 Mean = 15.25 Caffeine 12 12 14 13 6 18 14 16 10 15 10 Mean = 12.25 Table 1: Number of words recalled These data are recreated from the published summary statistics and are estimates of the actual data. Click here to access StatKey. (a) State the null and alternative hypotheses. Let group 1 be the group where the words are recalled after sleep and let group 2 be the group where words are recalled after caffeine. : - :* * = \\u = \\mul : \\mu2 #p #p1 :p2 :: - : Who :: \\overline(x] :: \\overline(x]_1 :: \\overline(x]_2 :: \\overset[\\wedge][p] # \\overset[\\wedge][p]_1 : loverset(\\wedge](p] 2 # r Ho: VS Ha: C ICALWUUR allu IVItuId b) What statistic will we record for each of the simulated samples, to create the randomization distribution? : - 8 * : 2: \\u 2: \\mu.1 8: \\mu.2 2: p 8 p.1 8 p 2 :: - : Who # \\overline(x] # \\overline(x]_1 # \\overline(x]_2 # \\overset[\\wedge][p] # \\overset[\\wedge][p]_1 Sample statistic: e Textbook and Media (c) What is the value of that statistic (stated in part (b)) for the observed sample? value = i eTextbook and Media (d) Where will the randomization distribution be centered? center = i e Textbook and Media (e) Find one point on the randomization distribution by randomly dividing the 24 data values into two groups. Compute the sample mean in each group, and compute the difference in the sample means for this simulated result. Round your answer to the nearest integer. The difference in the sample means is e Textbook and Media (f) Use Statkey or other technology to create a randomization distribution. Estimate the p-value for the observed difference in means given in part (b) and part (c). Round your answer to two decimal places. The p-value is e Textbook and Media (g) At a significance level of a = 0.01, what is the conclusion of the test? O Do not reject Ho, there is no evidence of a difference in memory ability between people who sleep and people who have caffeine. O Reject Ho, there is a difference in memory ability between people who sleep and people who have caffeine. O Do not reject Ho, there is a difference in ple who sleep and people who have caffeine. O Reject Ho, there is no evidence of a difference in m between people who sleep and people who have caffeine. e Textbook and Media
