A quality control supervisor wishes to determine whether the following measurements are random: For this purpose,the supervisor computes the median of the thirty observations above and compares each measurement to the median to perform a runs test.She uses a significance level of 0.05.This is a ______ test and the critical ______.
A) one-tailed; value is 1.96
B) one-tailed; value is 1.645
C) two-tailed; values are ±1.96
D) two-tailed; values are ±1.645
E) one-tailed; value is −1.96

Question

A quality control supervisor wishes to determine whether the following measurements are random:  For this purpose,the supervisor computes the median of the thirty observations above and compares each measurement to the median to perform a runs test.She uses a significance level of 0.05.This is a ______ test and the critical ______.
A) one-tailed; value is 1.96 
B) one-tailed; value is 1.645 
C) two-tailed; values are ±1.96 
D) two-tailed; values are ±1.645 
E) one-tailed; value is −1.96

Quizplus · Accepted Answer

The runs test is a two-tailed test used to determine whether a set of data is random or not. The critical values for a runs test at a significance level of 0.05 are ±1.96. Therefore, the correct choice is (C).

A Quality Control Supervisor Wishes to Determine Whether the Following