Southern Connecticut State University

ECO 221

Class Problem 10 (2) Chapter 10

ECO 221: Statistics for Economics
1. Over the past year, the vice president of 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. State your
findings and conclusions in a report to the VP of human resource from the following
results:

2. The results of a study conducted as part of a yield-improvement effort at a semiconductor
manufacturing facility provided defect data for a sample of 450 wafers. The following
contingency table presents a summary of the responses to two questions:
 “Was a particle found on the die that produced the wafer?”
 “Is the wafer good or bad?”