A education researcher measured the IQ test scores of 78 seventh-grade students in a rural school, and also their school grade point average (GPA) measured on a 12-point scale. Here is a graph of GPA versus IQ for these students: The line drawn on the graph is the least-squares regression line of GPA on IQ. Use this line to predict the GPA of a student with IQ 110. Your prediction is GPA about
A) 1.7.
B)6)
C) 7.5.
D) 9.

Question

A education researcher measured the IQ test scores of 78 seventh-grade students in a rural school, and also their school grade point average (GPA) measured on a 12-point scale. Here is a graph of GPA versus IQ for these students:  The line drawn on the graph is the least-squares regression line of GPA on IQ. Use this line to predict the GPA of a student with IQ 110. Your prediction is GPA about
A) 1.7. 
B)6) 
C) 7.5. 
D) 9.

Quizplus · Accepted Answer

According to the graph, if a student has an IQ of 110, the predicted GPA is approximately 7.5, which is closest to option C. This can be found by tracing a line straight up from 110 on the x-axis until it hits the least-squares regression line, and then tracing horizontally to the y-axis to read the predicted GPA.

A Education Researcher Measured the IQ Test Scores of 78