Over the past year, the vice president for human resources at a large medical center has run a series of three-month workshops aimed at increasing worker motivation and performance. To check the effectiveness of the workshops, she selected a random sample of 35 employees from the personnel files and recorded their most recent annual performance ratings, along with their ratings prior to attending the workshops. If the vice president for human resources wishes to assess the effectiveness of the workshop in improving performance ratings, what sort of test should she use?

She should use THE PAIRED SAMPLE T-TEST.

Step-by-step explanation: The Paired sample t-test, is a method used in statistics to determine whether the mean difference in a statistics is zero. Which shows the accuracy of the two different recorded observation.

The paired sample t-test will help her to evaluate the recorded performance rating of the workers before the workshop, and after attending the workshop.

Example:

Let the mean in the workers performance rating before the workshop be Mb, and after the worship be Ma.

If she wants to find how significant the workshop was.

Ma - Mb = 0 means the workshop did not have any influence in their performance, as their performance remains the same.

Ma - Mb > 0 means that the workshop has improved the performance of the workers. As their mean performance after the workshop is greater than their mean performance before the workshop.

Ma - Mb <0 means that the workshop has reduced the performance of the workers. As their mean performance before the workshop is greater than their mean performance after the workshop.