Economics and Finance
Online investing has grown with the Internet and with companies like E*TRADE and Ameritrade. Independent random samples of investors were obtained and asked whether they traded online within the past year. The data are given in the following table, by portfolio size.
a. Compute the sample proportions and verify the nonskewness criterion.
b. Construct a 95% confidence interval for the difference in population proportions of online investors.
c. Using the interval in part (b), is there any evidence to suggest that the population proportion of online investors is different for these two portfolio classifications? Justify your answer.