# Question: In Exercise 11 39 we tested to determine whether the installation

In Exercise 11.39, we tested to determine whether the installation of safety equipment was effective in reducing person-hours lost to industrial accidents. The null and alternative hypotheses were

H0: μ = 0

H1: μ < 0

With σ = 6, α = .10, n = 50, and μ = the mean percentage change. The test failed to indicate that the new safety equipment is effective. The manager is concerned that the test was not sensitive enough to detect small but important changes. In particular, he worries that if the true reduction in time lost to accidents is actually 2% (i.e., μ = −2), then the firm may miss the opportunity to install very effective equipment. Find the probability that the test with σ = 6, α = .10, and n = 50 will fail to conclude that such equipment is effective. Discuss ways to decrease this probability.

H0: μ = 0

H1: μ < 0

With σ = 6, α = .10, n = 50, and μ = the mean percentage change. The test failed to indicate that the new safety equipment is effective. The manager is concerned that the test was not sensitive enough to detect small but important changes. In particular, he worries that if the true reduction in time lost to accidents is actually 2% (i.e., μ = −2), then the firm may miss the opportunity to install very effective equipment. Find the probability that the test with σ = 6, α = .10, and n = 50 will fail to conclude that such equipment is effective. Discuss ways to decrease this probability.

**View Solution:**## Answer to relevant Questions

The test of hypothesis in the SSA example concluded that there was not enough evidence to infer that the plan would be profitable. The company would hate to not institute the plan if the actual reduction was as little as 3 ...a. The mean and standard deviation of a sample of 100 is x̄ = 1500 and s = 300. Estimate the population mean with 95% confidence.b. Repeat part (a) with s = 200.c. Repeat part (a) with s = 100.d. Discuss the effect on the ...a. Calculate the test statistic when x̄ = 145, s = 50, and n = 100. Use a 5% significance level.H0: µ = 150H1: µ < 150b. Repeat part (a) with x̄ = 140.c. Repeat part (a) with x̄ = 135.d. What happens to the t-statistic ...a. A random sample of 11 observations was taken from a normal population. The sample mean and standard deviation are x̄ = 74.5 and s = 9. Can we infer at the 5% significance level that the population mean is greater than ...A random sample of American adults was asked whether or not they smoked cigarettes. Those who responded affirmatively were asked how many cigarettes they smoked per day. Assuming that there are 50 million American adults who ...Post your question