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
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 end points 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.
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