(b) Employers at a firm are worried about the effect of March Madness, a basketball championship held each spring in the US, on
employee productivity. They estimate that on a regular business day employees spend on average 15 minutes of company time checking personal email, making personal phone calls, etc. They also collect data on how much company time employees spend on such non-business activities during March Madness. They want to determine if these data provide convincing evidence that employee productivity changed during March Madness. In symbols, the hypotheses are:
