An army depot that overhauls ground mobile radar systems is interested in improving its processes.One problem involves troubleshooting a particular component that has a high failure rate after it has been repaired and reinstalled in the system.The shop floor supervisor believes that having standard work procedures in place will reduce the time required for troubleshooting this component.Time (in minutes) required troubleshooting this component without and with the standard work procedure is recorded for a sample of 19 employees.In order to determine if having a standard work procedure in place reduces troubleshooting time, they should use ________________________ .
A)a one-tailed paired t-test
B)a two-tailed test of two independent means
C)a one-tailed test of two independent means
D)a two-tailed paired t-test
E)a test of two proportions

Question

Quizplus · Accepted Answer

DA one-tailed paired t-test is appropriate because the hypothesis specifically predicts a direction of change (reduction in time) and involves comparing the same group (the 19 employees) before and after implementing the standard work procedure, indicating paired data. A two-tailed paired t-test is also correct because it allows for testing the difference in means without specifying the direction of change, which is suitable for examining the effect of the standard work procedure on troubleshooting time, again with paired data.

An Army Depot That Overhauls Ground Mobile Radar Systems Is