Question

An instructor for a class collected data from one of her class to investigate the relationship between X: study time (per week) and Y: college GPA. She has fitted the simple linear regression model as:

G P A = 2.652 + 0.04391 × S t u d y t i m e

What can you say about the slope β₁?

a.) One unit change in study time will increase the GPA by 0.04391 unit.

b.) One unit change in study time will decrease the GPA by 0.04391 unit.

c.) If study time is 0, then the GPA owned will be 2.652.

d.) Cannot be determined.

An engineering student has designed a new cloths dryer. X: temperature setting in ∘F, Y: actual interior temperature during cycle ∘F. She has collected the following n=5 samples:

X	Y
140	170
145	174
150	172
155	178
160	176

Find the correlation coefficient, r.

a.) 0.80

b.) 0.70

c.) 0.90

d.) 0.70

Answer 1

Answer - 1: The true statement about slope is:

One unit change in study time will increase the GPA by 0.04391 unit.

Option A is correct.

Answer - 2: The statistical software output for this problem is:

From above output:

Correlation coefficient = 0.80

Option A is correct.