Note: since this is part of exam 2, you are to work individually on these problems. Do not discuss these questions with anyone except Dr. Williams. Work each problem on a separate page, bring the take home problems (and all intermediate calculations) with you to the in-class exam on Friday, April 3. One or more of these problems will be handed in with the in-class exam, and information from others will be used on some of the in-class questions.
1. A guitar store only sells guitars made by three companies: Gibson, Ibanez, and Taylor. A separate random sample was taken of the guitars for sale from each company. Use this information to calculate an estimate of the average guitar price at the store, and an error bound for your estimate. What sample size should we take in a future sample (and how would we allocate it among companies) to achieve an error bound of $200?
Martin Van Buren 56.0 William McKinley 57.0 William Henry Harrison 68.0 Jimmy Carter 69.0 Theodore Roosevelt 70.0 Grover Cleveland 71.0 James Buchanan 72.0 John F. Kennedy 72.0 Andrew Jackson 73.0 George H.W. Bush 74.0 Abraham Lincoln 76.0
a) From this data, estimate the average height of
b) Which variance estimator is more appropriate for these data?
4. For the housing data in problem 2, can you think of a way to design a future sampling study to have a lower error bound? (For example, how could more information be used?)