Display 9.47 shows a random sample of 7 seasons taken from the 128 seasons of Los Angeles rainfall in E49.
a. Assuming you havenâ€™t seen the population in E49, are the conditions met for constructing a confidence interval for mean seasonal rainfall?
Â b. Regardless of your answer in part a, construct a 95% confidence interval.
c. The mean seasonal rainfall is 15.06 in. Did you capture the true mean in your confidence interval in part b?
Â d. Is the skewed shape of the population reflected in this small sample? If you take the log of each rainfall amount, are the conditions for inference better satisfied or worse? (What to do when you have a small sample isnâ€™t always clear. Fortunately, the t-procedure is fairly robust.)