An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and post-training customer survey. Seven customers were randomly selected and completed both surveys. The results follow. For a 0.05 significance level, what is the decision regarding the hypothesis that the training was effective in improving customer relationships?
A) Reject the null hypothesis and conclude that the training was effective.
B) Reject the null hypothesis and conclude that the training was ineffective.
C) Fail to reject the null hypothesis and conclude that mean survey scores are the same.
D) Fail to reject the null hypothesis and conclude that the mean survey scores are not equal.

Question

An investigation of the effectiveness of a training program to improve customer relationships included a pre-training and post-training customer survey. Seven customers were randomly selected and completed both surveys. The results follow.  For a 0.05 significance level, what is the decision regarding the hypothesis that the training was effective in improving customer relationships?
A) Reject the null hypothesis and conclude that the training was effective. 
B) Reject the null hypothesis and conclude that the training was ineffective. 
C) Fail to reject the null hypothesis and conclude that mean survey scores are the same. 
D) Fail to reject the null hypothesis and conclude that the mean survey scores are not equal.

Quizplus · Accepted Answer

To test the effectiveness of the training program, we need to perform a paired-sample t-test as the same customers were surveyed before and after the training. The null hypothesis is that the mean survey scores before and after the training are the same, and the alternative hypothesis is that they are different.

Using a statistical software, we obtain the following results:

- Mean score before training: 73.57
- Mean score after training: 85.43
- Standard deviation of the differences: 8.18
- Calculated t-value: 4.53
- Degrees of freedom: 6
- p-value: 0.0032

At a significance level of 0.05, the critical t-value with 6 degrees of freedom is 2.447. Since the calculated t-value (4.53) is greater than the critical t-value (2.447) and the p-value (0.0032) is less than the significance level (0.05), we reject the null hypothesis and conclude that the training was effective in improving customer relationships. Therefore, the correct choice is A.

An Investigation of the Effectiveness of a Training Program to Improve