Homework Assignment VI
Solve the problems in the POSIDON, INC case module on page 184 of the textbook. [Remark]: You only need to answer the questions, rather than prepare a case write-up. The Excel file “Homework6-1_POSIDON.xls” containing the data for the case has been uploaded to the MBA portal.
Finish the following exercise:
E1. A study by the Center for Disease Control (CDC) found that 23.3% of adults are smokers and that roughly 70% of those who do smoke indicate that they want to quit (Associate Press, July 26, 2002). CDC reported that, of people who smoked at some point in their lives, 50% have been able to kick the habit. Part of the study suggested that the success rate for quitting rose by education level. Assume that a sample of 100 college graduates who smoked at some point in their lives showed that 64 had been able to successfully stop smoking. (a) State the hypotheses that can be used to determine whether the population of college graduates has a success rate higher than the overall population when it comes to breaking the smoking habit. (b) Given the sample data, what is the proportion of college graduates who, having smoked at some point in their lives, were able to stop smoking? Construct a 95% confidence interval for the proportion. (c) What is the p-value? At = 0.01, what is your hypothesis testing conclusion? E2. The demand of a certain kind of pen in Fudan student supermarket last year obeys a distribution with an average 27 per day. This year the price of such pen decreases by ￥0.5. A random sample containing 6 days’ purchase amount is recorded. The data is 29, 28, 31, 26, 27 and 30. The manager hopes to know if the average demand of such pen increases this year. Could you offer any suggestion? Write down the necessary assumptions for your suggestion. (Hint: Use hypothesis test.) [Remark]: Homework assignment VI is due on November 21 during the lecture. 1