Linear Regression Jeopardy!

Residuals

100

What is the equation for the residual?

Residual = actual y - predicted y

200

With an observed value of 25.8 and a predicted value of 45.9, what is the residual?

-20.1

300

What does a negative residual indicate - where is the observed value in comparison to the predicted value?

The observed is below the predicted value.

400

Linear model A creates a sum of least squares with an average residual of 1,500 and B creates an average of 480. Which model should you use? Why?

Model B - it's lower.

500

The linear model for a local store's Number of Sales people working versus Sales is as follows: Sales = 8,106 + 91.34x. If two people are working, the observed value is $8600. What is the residual?

$311.32

Linear Equation

100

What is the equation for linear regression?

y = ax+b

or

y = mx+b

200

Predicted Price = 18.617 + 103.929x. This is the regression equation for disk space Capacity (in megabytes) versus Price at a local store. With a capacity of 2 mb, what would you expect the price to be?

$226.475

300

Explain in words what the slope of the regression line allows us to do

What a predicted response variable (y) should be for a given explanatory variable (x)

400

The linear model for a local store's Number of Sales people working versus Sales is as follows: Sales = 8,106 + 91.34x. With 14 people working, what would you expect sales to be?

$9,384.76

500

An analysis of Math SAT versus Verbal SAT scores gives an equation of Predicted Verbal SAT Score = 171.333 + 0.6943x. What would you predict someone's verbal score to be if they got a 520 on their Math section?

532.369

Analyzing Dot plots

100

Would a Scatter plot with a high number of outliers have a strong or a weak correlation to its line of best fit?

weak

200

For the Scatter plot shown, how would you describe its Direction (Positive, Negative or No Correlation)?

Positive

300

For the Scatter Plot shown, how would you describe the correlation between the data points and the shown line of best fit? (Strong or Weak)

Weak

400

True or False: This Residual Plot would correspond with a good line of best fit for the original data

False

500

State whether or not you could feel confident about your line of best fit representing your data if you saw the following scatter plot and residual plot? Be sure to explain why.

Yes, I could feel confident because the resulting residual plot shows no remaining shape/trend and has a random scattering of residuals