Matched or Paired Samples · Exercise 21

A golf instructor is interested in determining if her new technique for improving players’ golf scores is effective. She takes four new students. She records their 18-hole scores before learning the technique and then after having taken her class. She conducts a hypothesis test. The data are as follows.

$$\begin{array}{ccccc}& \text{Player 1}& \text{Player 2}& \text{Player 3}& \text{Player 4}\\ \text{Mean score before class}& \text{83}& \text{78}& \text{93}& \text{87}\\ \text{Mean score after class}& \text{80}& \text{80}& \text{86}& \text{86}\end{array}$$
The correct decision is:

(a) Reject H_0.
(b) Do not reject the H_0.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Introductory Statistics 2e · §10.4 Matched or Paired Samples · Exercise 21