An eccentric professor believes that a child with an IQ 100should have a reading test score 50and that the reading score should increase by 1 a point for every additional point of IQ. What is the equation of the professor’s regression line for predicting reading scores from IQ?

Short Answer

Expert verified

The equation isy^=x-50.

Step by step solution

01

Given Information

We have,

x=IQ score starting from 100

Reading test scorelocalid="1649920422526" =50

y=reading test score

The reading test score yincreases by 1a point per every additional point of IQx:

y^=a+1x=a+x

with asome constant.

02

Explanation

The reading test score for a child with an IQ of 100may be 50, depending on the IQ of the child.

We needy=50whenx=100.

Analyze the equation at x=100:

localid="1650004532020" y^=a+x=a+100

We needy=50when x=100so,

a+100=50

Subtract the equation with100,

localid="1650004514276" a=50-100=-50

Accordingly, the equation for predicting reading scores from IQ using the professor's regression line is:

localid="1650004499566" y^=a+x=-50+x=x-50

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