Quiz 3.2: Least Squares Regression spring2021

What is the formula for the regression line?

• y=mx+b

• 
  

  $y^{\wedge}=ax+b$

• y=m+bx

• $y^{\wedge}=a+bx$

Tags

CCSS.8.F.B.4

CCSS.HSF.LE.A.2

Y-hat is the ________ value of y for a given value of x.

• predicted

• slope

• y-intercept

Tags

CCSS.HSF.LE.B.5

_____________________ is the use of a regression line for prediction outside the interval of x values used to obtain the line.

• Residual

• Extrapolation

• Prediction

• Residual Plot

Tags

CCSS.8.SP.A.3

To make a prediction using the regression line, you would...

• plug in a predicted guess for y-hat and simplify

• look at the scatterplot

• rearrange the equation to solve for x

• plug in a value for x and simplify

Tags

CCSS.HSF.IF.A.2

What is a residual?

• the difference between the observed value of y and the predicted value of y by the regression line

• the sum of the observed value of y and the predicted value of y by the regression line

• the difference between the actual value of x and the value of x predicted by the regression line

• the sum of the the actual value of x and the value of x predicted by the regression line

Tags

CCSS.HSS.ID.B.6B

A ______________ regression line makes the residuals as small as possible.

• good

• bad

• ugly

• mean

Tags

CCSS.HSS.ID.B.6B

How do you calculate a residual?

• Observed - Predicted
• Predicted - Observed

Tags

CCSS.HSS.ID.B.6B

The ___________________ measures the percent of the variability in the response variable that is accounted for by the least-squares regression line.

• residual

• extrapolation

• coefficient of determination

• regression line

Data was collected on the weight of a male laboratory rat for the first 25 weeks after its birth. The linear regression equation is y= 100 + 40x, where x is number of weeks and y is weight in grams. What does the y-intercept mean in the context of this problem?

• The predicted weight of the rat in 40 years.

• The predicted weight of the rat at birth.

• The current weight of the rat.

• The average increase in the rat's weight.

Tags

CCSS.HSF.LE.B.5

A restaurant sells pizza for the prices in the data table. Calculate the linear regression equation of the data.

• y = 12 + 1.5x

• y = 1.5 + 12x

• y = -8 + 0.67x

• y = 0.67 -8x