Answer: 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.