TABLE 11-4
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 11-4, the degrees of freedom of the test statistic is ________.
A) 4
B) 8
C) 10
D) 448

Question

TABLE 11-4
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 11-4, the degrees of freedom of the test statistic is ________.
A) 4 
B) 8 
C) 10 
D) 448

Quizplus · Accepted Answer

The degrees of freedom for the test statistic is the number of observations minus the number of parameters estimated. In this case, we have 449 observations and we are estimating 1 parameter (the mean). Therefore, the degrees of freedom is 449 - 1 = 448.

TABLE 11-4 A Computer Used by a 24-Hour Banking Service Is Supposed