A researcher plans to conduct a study to compare two groups.Based on previous research,she anticipates a medium effect size.She does a power analysis with alpha level of .05.This power analysis tells her
A) the t-test outcome and degrees of freedom she should expect.
B) Cohen's d for her study.
C) the sample size she will need to observe a statistically significant finding.
D) the practical significance of her research.

Question

Quizplus · Accepted Answer

A power analysis helps to determine the sample size needed to observe a statistically significant result. By setting a desired level of power (usually 0.80 or higher) and effect size, the power analysis can estimate the minimum sample size needed to detect a true difference between groups. In this case, the researcher anticipates a medium effect size and sets the alpha level at 0.05, so the power analysis will estimate the necessary sample size to detect this effect with a specified level of power.

A Researcher Plans to Conduct a Study to Compare Two