Suppose that you wish to obtain a confidence interval for a population mean. Under the conditions described below, should you use the z-interval procedure, the t-interval procedure, or neither?
- The population standard deviation is known.
- The population is far from being normally distributed.
- the sample size is large.
A)Neither
B)t-interval procedure
C)z-interval procedure

Question

Suppose that you wish to obtain a confidence interval for a population mean. Under the conditions described below, should you use the z-interval procedure, the t-interval procedure, or neither?
- The population standard deviation is known.
- The population is far from being normally distributed.
- the sample size is large. 
A)Neither
B)t-interval procedure
C)z-interval procedure

Quizplus · Accepted Answer

The z-interval procedure is appropriate when the population standard deviation is known and the sample size is large, even if the population is not normally distributed. The large sample size allows for the use of the Central Limit Theorem, which states that the sampling distribution of the sample mean will be approximately normally distributed regardless of the population distribution.

Suppose That You Wish to Obtain a Confidence Interval for a Population