A local trucking company fitted a regression to relate the t

A local trucking company fitted a regression to relate the travel time (days) of its shipments as a function of the distance traveled (miles). The fitted regression is Time = -7.126 + .0214 Distance, based on a sample of 20 shipments. The estimated standard error of the slope is 0.0053. Find the critical value for a right-tailed test to see if the slope is positive, using = .05.

a. 2.101

b. 2.552

c. 1.960

d. 1.734

Solution

Answer to the question)

Since it is a right tailed test with alpha = 0.05

df = n-2

df = 20-2 = 18

we get

=t.inv(0.05,18) is the excel command that returns the T critical value

We Get T = 1.734