Due to a budget consideration, a researcher is asked to decrease the number of subjects in an experiment. Which of the following will occur?
A) Situation I: The margin of error for a 95 percent confidence will increase.
B) Situation II: The margin of error for a 95 percent confidence will decrease.
C) Situation III: The P-value of a test, when the null hypothesis is false and all facts about the population remain unchanged as the sample size increases, will increase.
D) Situation IV: The P-value of a test, when the null hypothesis is false and all facts about the population remain unchanged as the sample size increases, will decrease.
E) Situation I and III are both correct.

Question

Quizplus · Accepted Answer

Decreasing the number of subjects in an experiment will increase the margin of error for a 95 percent confidence interval (Situation I) because the sample size is inversely related to the margin of error. Additionally, if the null hypothesis is false and all facts about the population remain unchanged, reducing the sample size would actually increase the P-value of a test (Situation III), making it harder to reject the null hypothesis due to decreased statistical power.

Due to a Budget Consideration, a Researcher Is Asked to Decrease