When determining the sample size,the standard deviation may not be known.Which of the following was not mentioned in your text as a way to estimate the standard deviation?
A)consult secondary sources
B)estimate based on researcher judgment
C)estimate from the mean
D)conduct a pilot study

Question

Quizplus · Accepted Answer

Estimating the standard deviation from the mean is not a valid method because the standard deviation measures the dispersion of data points around the mean, and cannot be directly inferred from the mean itself.

When Determining the Sample Size,the Standard Deviation May Not Be