SCENARIO 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 Scenario 12-4, which test would be used to properly analyze the data in this experiment?
A) test of independence
B) test for difference among more than two proportions
C)Wilcoxon rank sum test
D)Kruskal-Wallis rank Test

Question

SCENARIO 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 Scenario 12-4, which test would be used to properly analyze the data in this experiment?
A) test of independence 
B) test for difference among more than two proportions 
C)Wilcoxon rank sum test 
D)Kruskal-Wallis rank Test

Quizplus · Accepted Answer

The proper test to use in this scenario would be a test for the difference among more than two proportions, as the manager wants to compare the proportion of errors in transactions assigned to each of the 5 memory locations. The Kruskal-Wallis and Wilcoxon rank sum tests are not appropriate for analyzing proportions. The test of independence would only be appropriate if the manager was interested in determining whether there was a relationship between the two variables - memory location and errors - but there is no indication that this is the case in the scenario. Therefore, the best choice is B: test for difference among more than two proportions. The test for difference among more than two proportions (also known as the chi-squared test for independence) would be used to analyze the data in this experiment, as it allows for the comparison of multiple proportions between groups. In this case, the groups are the 5 memory locations and the proportion of errors in transactions assigned to each location is being compared.

SCENARIO 12-4 a Computer Used by a 24-Hour Banking Service