Least-Squares Regression Lines
Interpreting
Residuals
100

When x increases by 1, we expect y to increase by m.

The slope

100

What is the direction of this linear regression?

Negative

100

How do you calculate a residual?

Actual-Predicted

200

When x=0, we expect the y-value to be a.

Y-intercept

200

What is the strength of this linear regression?

Moderate

200

Use the point (7,4) to find the residual for the linear regression.

-1.5918

300

DOFS is an acronym to help us remember these four things about a scatterplot.

Direction

Outliers

Form

Strength

300

Interpret the y-intercept of the least-squares regression line.

When x is 0, we expect y to be 6.57110

300

Use the residual plot to determine if the linear regression model is a good fit for the data.

Yes.

400

represents this measurement about a least-squares regression line.

Standard Deviation of the Residuals

400

Interpret the slope of this linear regression.

When x increases by 1, we expect y to decrease by 0.1399.

400

Does the residual plot indicate this is a good model for the data?

No

500

___ % of the variation in y can be explained by the x-variable.

r^2

500

Interpret r^2 for this linear regression.

24% of the variability in y can be explained by the x-variable.

500

Which residual plot does NOT represent a good model?

The middle plot