Question

Bank of America's Consumer Spending Survey collected data on annual credit card
charges in seven different categories of expenditures: transportation, groceries, dining
out, household expenses, home furnishings, apparel, and entertainment. Using data from
a sample of 42 credit card accounts, assume that each account was used to identify the
annual credit card charges fbr groceries (population 1) and the annual credit card charges
for dining out (population 2). Using the difference data, the sample mean difference was
d = $850, and the sample standard deviation was sd = $1123.
a.   Fonnulate the null and alternative hypotheses to test for no difference between the
population mean credit card charges for groceries and the population mean credit card
charges for dining out
b.   Use a .05 level of significance. Can you conclude that the population means di「
fer? What is the p-value?
c.   Which category, groceries or dining out, has a higher population mean annual credit
card charge? What is the point estimate of the difference between the population
means? What is the 95% confidence interval estimate of the difference between the
population means?

Answer 1