Question

An instructor computed a least squares regression line to predict final course percentage based on Exam 1. She got the following formula: yhat=34.28+0.5897x. Suppose that a student who made a grade of 76 on Exam 1 had a final percentage grade of 71.66%. What is the residual?

Answer 1

Answer:

8.0372

Step-by-step explanation:

given that an instructor computed a least squares regression line to predict final course percentage based on Exam 1.

The regression equation was found out as

$y hat = 34.28+0.5897x$

When a student makes a grade of 76 one exam 1, and 71.66% in final exam we have

$x = 76 and y = 71.66$

Substitute to get the estimated y as per regression line as

$y hat =34.28+0.5897(76)\\=79.0972$

Residual = difference between y hat and y

= $|79.0972-71.66|\\= 8.0372$