TABLE 13-12
The manager of the purchasing department of a large banking organization would like to develop a model to predict the amount of time (measured in hours) it takes to process invoices. Data are collected from a sample of 30 days, and the number of invoices processed and completion time in hours is recorded. Below is the regression output:
Note: 4.3946E-15 is 4.3946×10 -15

-Referring to Table 13-12, the degrees of freedom for the F test on whether the number of invoices processed affects the amount of time are
A) 1, 28.
B) 1, 29.
C) 28, 1.
D) 29, 1.

Question

TABLE 13-12
The manager of the purchasing department of a large banking organization would like to develop a model to predict the amount of time (measured in hours) it takes to process invoices. Data are collected from a sample of 30 days, and the number of invoices processed and completion time in hours is recorded. Below is the regression output:
  Note: 4.3946E-15 is 4.3946×10 -15 
  
-Referring to Table 13-12, the degrees of freedom for the F test on whether the number of invoices processed affects the amount of time are
A) 1, 28. 
B) 1, 29. 
C) 28, 1. 
D) 29, 1.

Quizplus · Accepted Answer

The degrees of freedom for the F test in a simple linear regression are (1, n-2), where n is the number of observations. If there are 30 observations, then the degrees of freedom are (1, 28).

TABLE 13-12 The Manager of the Purchasing Department of a Large Banking