In: Statistics and Probability
The regression equation is Ŷ = 30 + 2.56X, the sample size is 14, and the standard error of the slope is 0.97. What is the critical value to test the significance of the slope at the 0.05 significance level?
Multiple Choice z = ±1.96
t = ±2.179
t = ±2.145
t = +2.145
Answer :
t = 2.179
To test the significance of the slope :
Ho: Slope of the regreesion equation is zero
H1: Slope of the regreesion equation is not zero
Two tailed test.
t-test is appropriate and degrees of freedom=n-2;
Given,
= 0.05; n=14; Degrees of freedom=n-2=14-2=12;
For two tailed test:
= 0.05; /2 = 0.05/2=0.025
critical values are :
t/2 = t0.025 ;
For 12 degrees of freedom, t0.025 = 2.179
Critcal values: t =2.179
Answer :
t = 2.179