A regression analysis between weight (y in kg) and height (x in cm) resulted in the following least-squares line: = -20 + 0.5x. Taking this into consideration, if the height is increased by 1 cm, what does this imply about the change in the weight, on average?
A) The weight will increase by 1/2 kg.
B) The weight will increase by 6 kg.
C) The weight will decrease by 1/2 kg.
D) The weight will decrease by 20 kg.

Question

A regression analysis between weight (y in kg) and height (x in cm) resulted in the following least-squares line:  = -20 + 0.5x. Taking this into consideration, if the height is increased by 1 cm, what does this imply about the change in the weight, on average?
A) The weight will increase by 1/2 kg. 
B) The weight will increase by 6 kg. 
C) The weight will decrease by 1/2 kg. 
D) The weight will decrease by 20 kg.

Quizplus · Accepted Answer

According to the least-squares line, for every 1 cm increase in height, the weight increases by 0.5 kg on average. Therefore, if the height is increased by 1 cm, the weight will also increase, on average, by 0.5 kg.

A Regression Analysis Between Weight (Y in Kg) and Height