TABLE 11-10
One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. Since the job is repetitious, after the initial training period, any improvement due to a learning effect might be offset by a loss of motivation. A defect rate is calculated for each worker in a yearly evaluation. The results for 100 workers are given in the table below.

-Referring to Table 11-10, which test would be used to properly analyze the data in this experiment to determine whether there is a relationship between defect rate and years of experience?
A) χ² test for independence
B) χ² test for differences among more than two proportions
C) χ² test for variance
D) none of the above

Question

TABLE 11-10
One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. Since the job is repetitious, after the initial training period, any improvement due to a learning effect might be offset by a loss of motivation. A defect rate is calculated for each worker in a yearly evaluation. The results for 100 workers are given in the table below.
 
-Referring to Table 11-10, which test would be used to properly analyze the data in this experiment to determine whether there is a relationship between defect rate and years of experience?
A) χ² test for independence 
B) χ² test for differences among more than two proportions 
C) χ² test for variance 
D) none of the above

Quizplus · Accepted Answer

The χ² test for independence would be the best choice to analyze the data in this experiment to determine whether there is a relationship between defect rate and years of experience. This is because the χ² test for independence is used to determine whether there is an association between two categorical variables. In this case, the two categorical variables are defect rate (measured as a proportion) and years of experience (measured as an interval variable). The null hypothesis for this test would be that there is no relationship between the two variables, and the alternative hypothesis would be that there is a relationship.

TABLE 11-10 One Criterion Used to Evaluate Employees in the Assembly Section