For statistical inference about the mean of a single population when the population standard deviation is unknown, the number of degrees for freedom for the t-distribution is equal to n - 1 because we lose one degree of freedom by using the:
A)sample mean as an estimate of the population mean.
B)sample standard deviation as an estimate of the population standard deviation.
C)sample proportion as an estimate of the population proportion.
D)sample size as an estimate of the population size.

Question

Quizplus · Accepted Answer

We lose one degree of freedom by using the sample mean as an estimate of the population mean because we are estimating the population parameter based on the information in the sample. This reduces the amount of information available to us and affects the number of degrees of freedom in the t-distribution. The sample standard deviation, sample proportion, and sample size do not affect the degrees of freedom for the t-distribution.

For Statistical Inference About the Mean of a Single Population