Management: Intimidators and Stressors This problem is based on information regarding productivity in leading Silicon Valley companies (see reference in Problem 21). In large corporations, an “intimidator” is an employee who tries to stop communication, sometimes sabotages others, and, above all, likes to listen to him- or herself talk. Let x1 be a random variable representing productive hours per week lost by peer employees of an intimidator.

x1: 8 3 6 2 2 5 2 A “stressor” is an employee with a hot temper that leads to unproductive tantrums in corporate society. Let x2 be a random variable representing productive hours per week lost by peer employees of a stressor.

x2: 3 3 10 7 6 2 5 8 Use a calculator with mean and standard deviation keys to verify that x1 5 4.00, s1 < 2.38, x2 5 5.5, and s2 < 2.78.

(a) Assuming that the variables x1 and x2 are independent, do the data indicate that the population mean time lost due to stressors is greater than the population mean time lost due to intimidators? Use a 5% level of signifi cance.

(Assume that the population distributions of time lost due to intimidators and time lost due to stressors are each mound-shaped and symmetrical.)

(b) Find a 90% confi dence interval for m1  m2. Explain the meaning of the con fi dence interval in the context of the problem.