Question: Consider the dollar value (in thousands) of gifts returned to each of your department stores after the holiday season (Table):
a. Compute the standard deviation.
b. Interpret the standard deviation as a measure of the variation from one store to another.
c. Compute the standard error of the average and briefly describe its meaning.
d. Find the two-sided 95% confidence interval for the mean value of returned merchandise for all downtown stores.
e. The Association of Downtown Merchants had been expecting an average value of $10,000 of returned merchandise per store, since this has been typical in the past. Test to see if this year's average differs significantly from their expectation.