At the annual meeting of the Golf Equipment Manufacturer’s Association, a speaker made the claim that at least 30% of all golf clubs being used are knockoff clubs that look very much like the more expensive originals. This claim prompted the association to conduct a study to see if the problem was as big as the speaker said. Suppose a random sample of 400 golfers was selected. Out of the 400 golfers, data were collected from 294. Based on the golfer’s response to the question about the brand of clubs used, a determination was made whether the club was “original” or a “copy.” The data are in a file called Golf Survey.

a. Based on the sample data, what conclusion should be reached if the hypothesis is tested at a significance level of 0.05? Show the decision rule.

b. Determine whether a Type I or Type II error for this hypothesis test would be more serious. Given your determination, would you advocate raising or lowering the significance level for this test? Explain your reasoning.

c. Confirm that the sample proportion’s distribution can be approximated by a normal distribution.

d. Based on the sample data, what conclusion should be drawn about the use of knock-off clubs? Is the speaker’s statement justified?