In: Statistics and Probability
1. The oce manager at a real estate firm makes a pot of co↵ee every morning. The time before it runs out, y, in hours, depends on the number of persons x, working in the oce on that day. Suppose that the pairs of (x, y) values from n = 6 days are given in table below. Number of people, x 1 2 3 3 4 5 Time before co↵ee runs out, y 8 4 5 3 3 1 (a) Calculate the standard deviation of responses, s (follow steps on pages 88 and 89). (b) Calculate the 95% confidence interval for average number of hours when x⇤ = 4 people are working in the oce (follow steps on page 90). (c) Interpret your interval from part (b). 94 (d) Calculate and interpret the 95% prediction interval for the number of hours when x⇤ = 4 people are working in the oce (follow steps on page 91). (e) Interpret your interval from part (d). (f) Calculate r2 (follow steps on page 92). (g) Interpret r2. (h) Compute linear correlation coecient r (follow steps on page 93). (i) Interpret r.