Suppose a group of randomly selected people were asked how many text messages they sent in a day. Figure A shows a histogram of the results for the females.

a. Describe the shape of the histogram. Are there any outliers? Would it be more appropriate to compare means or medians if we wished to compare the typical number of messages sent by men with the typical number sent by women? Why?
b. Figure B shows the results of a Mann-Whitney test to determine whether the median number of messages sent by men differs from the number sent by women. Compare the sample medians descriptively.
c. Test the alternative hypothesis that the median for all women is larger than the median for all men, using a significance level of 0.05.
d. If a two-sided hypothesis had been used, what would the p-value and conclusion have been?

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30 25 20 15 5 0 0 50 100 150 200 Messages Sent by Females Mann-Whitney Test and cI: Send Female, Send Male N Nedian Send Female 48 Send Male 61 3:00 Point estimate for ETA1-ETA2 is 3.00 95.0 percent C1 for ETAI-ETA2 ǐe (-0.01, 9.01) W 2955.0 Test of ETILL ETA2 vs ETA! > ETA2 İB 8Īgnificant at 0.0274 The test is eignificant at 0.0269 adjusted for tieel