# Question

Consider the profits of the aerospace firms in the Fortune 500, shown in Table 16.4.2.

a. Draw a histogram of these profit percentages. Describe the distribution.

b. Find the average and the median. Explain why they are either similar or different.

c. Use the t test to see if the mean profit (for the idealized population of similar firms operating under similar circumstances) is significantly different from zero. (Use the t test for now, even if you feel it is inappropriate.)

d. Use the sign test to see whether the median profit of this idealized population is significantly different from zero.

e. Compare these two testing approaches to this data set. In particular, which of these two tests (t test or sign test) is appropriate here? Are both appropriate? Why?

a. Draw a histogram of these profit percentages. Describe the distribution.

b. Find the average and the median. Explain why they are either similar or different.

c. Use the t test to see if the mean profit (for the idealized population of similar firms operating under similar circumstances) is significantly different from zero. (Use the t test for now, even if you feel it is inappropriate.)

d. Use the sign test to see whether the median profit of this idealized population is significantly different from zero.

e. Compare these two testing approaches to this data set. In particular, which of these two tests (t test or sign test) is appropriate here? Are both appropriate? Why?

## Answer to relevant Questions

Of the 35 people in your sales force, more than half have productivity above the national median. The exact numbers are 23 above and 12 below. Are you just lucky, or is your sales force significantly more productive than the ...Use the data sets from problems 2 and 3, on profit as a percent of sales for building materials firms and for aerospace firms. a. Find the median profit for each industry group and compare them. b. Combine the two data sets ...a. For what kind of data set is the chi-squared test for equality of percentages appropriate? b. What are the reference values for this test? c. What are the hypotheses? d. How are the expected counts obtained? What do they ...A commercial bank is reviewing the status of recent real estate mortgage applications. Some applications have been accepted, some rejected, and some are pending while waiting for further information. The data are shown in ...Refer to the data for problem 5. a. What does the null hypothesis of independence claim, in practical terms, for this situation? b. How many managers responding “Worse” would you expect to find in this sample if response ...Post your question

0