Question

X	Y
9	-2.8
4	3.1
6	-4.9
2	1.2
8	-5.9

The sample of five observations for the variables x and y has been collected .

The least squares regression line for this sample is y = 4 − x.

 Draw a scatter plot for this dataset and add the regression line.  In this diagram, indicate the five residuals of this linear regression .  Calculate the predicted value and the residual for the point (6, −.9).

Answer 1

1.

scatter plot :

scatter plot with the regression line :

2.

Residuals :

X	Y	Y(regression) : (y=4-x)	residual = Y - Y(regression)
9	-2.8	-5	2.2
4	3.1	0	3.1
6	-4.9	-2	-2.9
2	1.2	2	-0.8
8	-5.9	-4	-1.9

3.

point (6,-4.9)

predicted value = 4-x = 4-6 = -2

predicted value = -2

residual = Y - Y(regression) = -4.9 - (-2) = -2.9

residual = -2.9

P.S. (please upvote if you find the answer satisfactory)