Question

A mom decided to bake cookies for her daughter's class 4th grade class each month. The teacher (who has an interest in statistics) collected data on how many minutes passed (x) versus how many cookies were left on the plate (y). When she performed a least squares regression, she obtained r = -0.87.Interpret the coefficient of determination (r^2).

Answer 1

Given:

r = -0.87

Find: r² and its interpretation

Solution:

$r^2=(-0.87)^2=0.7569$

Interpretation: This means that 75.69% of the dependent variable that is the number of cookies left on the plate can be predicted by the given number of minutes.