The data below represent the weight losses for people on three different exercise programs $$\begin{array} { c c c } \text { Exercise A } & \text { Exercise B } & \text { Exercise C } \ \hline 2.5 & 5.8 & 4.3 \ 8.8 & 4.9 & 6.2 \ 7.3 & 1.1 & 5.8 \ 9.8 & 7.8 & 8.1 \ 5.1 & 1.2 & 7.9 \end{array}$$ If we want to test the claim that the three size categories have the same means, why don't we use three separate hypothesis tests for $\mu$₁=$\mu$₂, $\mu$=$\mu$₃ , and $\mu$₁=$\mu$₃ ? A) Actually, we do want to use three separate hypothesis tests. B) The risk of type I error increases and becomes too high. C) The risk of type II error increases and becomes too high. D) A hypothesis test for comparing two means does not exist.

Question

Quizplus · Accepted Answer

Using multiple separate hypothesis tests increases the risk of committing a Type I error, which is falsely rejecting the null hypothesis. This is because each test adds to the overall chance of making this error across all tests conducted.

The Data Below Represent the Weight Losses for People on Three