Use the data from Example 8.11 involving citizens opinions about a bond proposal, reproduced here.

Find 99% confidence intervals for the proportion in the developing section favoring the proposal, and for the difference in the proportions favoring the proposal for the two sections of the city 1. Select stat ➤ TESTS and either A:1-PropZInt… or B:2-PropZInt. Enter the values for n1 and x1 (or n1, n2, x1, and x2) on the appropriate lines.
2. Change the value on the line marked “C-Level:” to 0.99, move your cursor to Calculate and press enter. The 99% confidence intervals for p1 and for p p 1 2 2 are shown in Figures 8.15

(a) and 8.15(b). (Notice that the hand calculations in Example 8.11 differ slightly in the third decimal place, due to rounding error in the value of z.005.)

Transcribed Image Text:

Developing Section Sample Size 50 Number Favoring Proposal 38 Rest of the City 100 65