The z-value needed to construct a 92.5% confidence interval estimate for the difference between two population proportions is:
A) 2.58
B) 2.33
C) 1.96
D) 1.78
E) 1.33

Question

Quizplus · Accepted Answer

For a 92.5% confidence interval, the z-value corresponds to the middle 92.5% of the standard normal distribution. This leaves 7.5% in the tails, or 3.75% in each tail. The z-value for 3.75% in the lower tail is approximately 1.78.

The Z-Value Needed to Construct a 92