TABLE 12-4
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of 5 memory locations. A check at the end of a day's transactions gave the counts shown in the table to each of the 5 memory locations, along with the number of reported errors.

The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the 5 memory locations differ.
-Referring to Table 12-4, which test would be used to properly analyze the data in this experiment?
A) X² test of independence
B) X² test for difference among more than two proportions
C) McNemar test for the difference between two proportions
D) McNemar test for the difference among more than two proportions

Question

TABLE 12-4
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of 5 memory locations. A check at the end of a day's transactions gave the counts shown in the table to each of the 5 memory locations, along with the number of reported errors.
  
The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the 5 memory locations differ.
-Referring to Table 12-4, which test would be used to properly analyze the data in this experiment?
A) X² test of independence 
B) X² test for difference among more than two proportions 
C) McNemar test for the difference between two proportions 
D) McNemar test for the difference among more than two proportions

Quizplus · Accepted Answer

The X² test for difference among more than two proportions is appropriate for analyzing the data in this experiment as there are more than two groups being compared (the 5 memory locations) and the researcher is interested in testing for differences in proportions (proportion of errors in each memory location). The X² test of independence is used when analyzing the relationship between two categorical variables, and the McNemar test is used when comparing two proportions for the same group. The McNemar test for the difference among more than two proportions is not a commonly used test and is not the best choice for this situation.

TABLE 12-4 A Computer Used by a 24-Hour Banking Service Is Supposed