The Business School Dean wants to determine if the future plans are significantly different for the three majors at a level of confidence of at least 90%. What test(s) would you recommend?
2. A company hired 20 salespeople and gave them an initial sales skills examination; test scores ranged from 68 to 95, with a mean of 79.4. All salespeople then attended a two-week training program and were re-tested; test scores ranged from 65 to 98, with a mean score of 83.2. The Corporate Training Director asked the Manager of Corporate Research whether the differences in the two test scores was significant, Due to EEO and other regulations, a confidence level of 99% is necessary. What hypothesis test(s) would you suggest to the Manager of Corporate Research?
3. An automobile manufacturer markets the same vehicle in Europe and the U.S., but buyer quality ratings are different. Based on a sample of 100 vehicles in each market, a mean quality rating of 4.3 was reported in the U.S. compared to a mean rating of 3.7 in Europe. What test(s) should be used to determine if there is a significant quality difference in the two markets, assuming that a significance level of 5% is required?
4. A political party suspects there are differences in Presidential candidate preferences based on age. A nationwide survey was conducted with 500 registered voters selected at random in each of four age groups (30 & under, 31-50, 51-70, over 70). All survey respondents indicated their preference rankings (1, 2, 3) for the party’s three leading candidates. To test differences in voting preferences, a significance level of .05 is desired. What test(s) would you recommend?
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