Chapter 8.3, Problem 17E

Testing the Difference Between Two Means In Exercises 9–20, (a) identify the claim and state H₀ and H_a, (b) find the critical value(s) and identify the rejection region(s), (c) calculate $\bar{d}$ and s_d, (d) find the standardized test statistic t, (e) decide whether to reject or fail to reject the null hypothesis, and (f) interpret the decision in the context of the original claim. Assume the samples are random and dependent, and the populations are normally distributed.

17. Product Ratings A company claims that its consumer product ratings (0–10) have changed from last year to this year. The table shows the company’s product ratings from the same eight consumers for last year and this year. At α = 0.05, is there enough evidence to support the company’s claim?