Question

A statistics instructor was interested in factors affecting student performance on exams. The instructor asked each student to honestly answer questions at the end of the exam regarding study time, number of other books used, GPA, and Age. The multiple regression output to predict exam grade was as follows:

	Coefficients	Standard Error	t Stat	P-value
Intercept	-60.9	40.6	-1.5	.268
Study Hours	-2.3	1.3	-1.8	.044
Other Books	2.4	0.9	2.7	.008
GPA	1.4	0.4	3.5	.096
Age	2.9	1.2	2.4	.024

                           
Excluding the constant term, which of the four independent variables are statistically significant in predicting exam grades? Use a 10% level of significance.

Answer 1

1) Study hours -

P value = 0.044 < 0.1 = alpha

Reject null hypothesis.

Study hours is statistically significant.

2) Other books :

P value = 0.008 < 0.1 = alpha

Reject null hypothesis.

Other books is Statistically significant.

3) GPA :

P value = 0.096 < 0.1 = alpha

Reject null hypothesis.

GPA is Statistically significant.

4) Age :

P value = 0.024 < 0.1 = alpha

Reject null hypothesis.

Age is Statistically significant.

( The null hypothesis that the coefficient is equal to zero. A low p-value (< 0.05) indicates that you can reject the null hypothesis. ) PL??