If a 90% confidence interval estimate for the difference between two population proportions is to be constructed, then the confidence coefficient would be:
A) .10
B) .90
C) .05
D) .45
E) .35

Question

Quizplus · Accepted Answer

The confidence coefficient represents the level of confidence in the interval estimate, and it is equal to 1 - alpha.

For a 90% confidence interval, the alpha level is 1 - 0.90 = 0.10. This means that we are willing to accept a 10% chance of making a type I error (rejecting the null hypothesis when it is true) in order to have a 90% chance of capturing the true difference between the two population proportions.

Therefore, the confidence coefficient is 0.90 or 90%. The correct choice is B.

If a 90% Confidence Interval Estimate for the Difference Between