Morning Routine A statistics student conducted a survey to determine how much time students at her school spent getting ready to leave the house after they got up in the morning. Figure A shows a histogram of the times for men. Assume that we have a random sample of 20 college men.

a. Figure B shows a 95% confidence interval for the mean time. Interpret the confidence interval, and explain why it might not be accurate.

b. After a log transform of the times is taken, a histogram of the log of the data suggests that the distribution of the transformed data is Normal. Figure C shows a 95% confidence interval for the log (base 10) of the times. Convert the boundaries back into minutes by raising 10 to the powers given as the endpoints of the confidence interval.
Interpret the confidence interval for the geometric mean.

c. Which interval is narrower?
d. Which interval would you report if the goal was to understand the typical amount of time spent getting ready in the morning for men at this college? Explain.

Transcribed Image Text:

20 40 60 80 100 Time for Men (minutes) One-Sample T: TimeMen Variable Men Mean StDev SE Mean 95% CI 20 37.25 19.77 4.42 (28.00, 46.50) One-Sample T: LogMen Variable N n StDev SE Mean LogMen 20 1.5223 0.2073 0.0464 (1.4253, 1.6193) 95% CI