Making Predictions from a Least-Squares Regression Line
Question 9 • DRHS GA-Statistical Reasoning
A statistics teacher was interested in the relationship between the number of days students waited to start a project and the score that project received (out of 100 points). Information was collected on several students and was used to obtain the regression equation ŷ = –3.64x + 96.5, where x represents the number of procrastination days and ŷ is the predicted grade. Which statement best describes the meaning of the slope of the regression line?
Answer
A
For each increase in number of procrastination days by 1, the predicted grade decreases by 3.64 points.
B
For each increase in number of procrastination days by 1, the predicted grade decreases by 96.5 points.
C
For each increase in grade by 1 point, the predicted number of procrastination days decreases by 96.5 days.
D
For each increase in grade by 1 point, the predicted number of procrastination days decreases by 3.64 days.