Suppose a 99% confidence interval for ? turns out to be (1000,2100) .If this interval was based on a sample of size n=23,explain what assumptions are necessary for this interval to be valid.
A) The sampling distribution of the sample mean must have a normal distribution.
B) The sampling distribution must be biased with 22 degrees of freedom.
C) The population of salaries must have an approximate t distribution.
D) The population must have an approximately normal distribution.

Question

Quizplus · Accepted Answer

The assumption necessary for the confidence interval to be valid is that the population from which the sample is drawn must have an approximately normal distribution, especially given the small sample size (n=23).

Suppose a 99% Confidence Interval for ? Turns Out to Be