The American Association of Individual Investors (AAII) conducts a weekly survey of its members to measure the percent who are bullish, bearish, and neutral on the stock market for the next six months. For the week ending March 27, 2019, the survey results showed 33.2% bullish, 39.6% neutral, and 27.2% bearish. Assume these results are based on a sample of 300 AAII members.
a. Over the long term, the proportion of bullish AAII members is .385. Conduct a hypothesis test at the 5% level of significance to see if the current sample results show that bullish sentiment differs from its long-term average of .385. What are your findings?
b. Over the long term, the proportion of bearish AAII members is .31. Conduct a hypothesis test at the 1% level of significance to see if the current sample results show that bearish sentiment is above its long-term average of .31. What are your findings?
c. Would you feel comfortable extending these results to all investors? Why or why not?