Interpret Regression Models

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= 40x+100, where x is number of weeks and y is weight in grams.

What does the y-intercept mean in context of the problem?

• The predicted weight of the rat in year one.

• The predicted weight of the rat at birth.

• The current weight of the rat.

• The average increase in the rat's weight.

Tags

CCSS.HSS.ID.C.7

The linear regression equation is y = 61.93x - 1.79. According to the model, the slope can be interpreted as:

• After 0 hours of driving, they went 61.93 miles.

• They drove at a speed of 61.93 miles per hour.

• They drove 61.93 miles total.

• They drove 61.93 hours total.

The equation y = -2x + 7 models the amount of gas remaining in a lawnmower after x hours of use since it was filled. What is the meaning of the slope?

• For each hour of mowing, the mower is predicted to use 2 gallons.

• the predicted amount of gas the lawnmower can hold is 2 gallons

• For every two hours of mowing, the mower is predicted to use 7 gallons.

• The predicted amount of gas remaining after 1 hour is 2 gallons.

Tags

CCSS.HSF.LE.B.5

CCSS.HSS.ID.C.7

Which choice correct describes the relationship between the two variables?

• As the number of people flying kites increases, the number of people playing volleyball increases.

• As the number of people flying kites increases, the number of people playing volleyball decreases.

• There is no relationship between the variables.

The scatter plot below shows the number of books read by students in Mrs. Hall’s English class and their final grades. Which statement represents the best description about the regression equation?

• The more books students read, the lower their English grade.

• The more books students read, the higher their English grade.

• The fewer books students read, the higher their English grade.

• No relationship exists between the number of books students read and their English grades.

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.7

Some data were collected on the weight of a male white laboratory rat for the first 25 weeks after its birth. The linear regression equation is (predicted weight)=100 + 40(time). Which is the best description of the slope for this regression equation in context of the problem?

• The slope of the line of regression is the time since birth of the rate. It demonstrates the predicted weight of a laboratory rate after so many months since birth.

• The slope is 40 grams/week which means the mouse gains about 40 grams per week after birth.

• The slope is 40 and it means for every increase in weeks the graph will increase.

• The slope is 40, which tells us the line increases.

Interpret the slope of the regression equation.

• Income increases by 31.45 with each additional hour worked.

• Income increases by 31.45

• As hours increases by one, income will increase by 31.45, on average

• As hours increases by one, income will increase by 31.45

Tags

CCSS.HSS.ID.C.7

Interpret the y - intercept for the linear regression equation

(predicted weight) = 100 + 40(age)

for the weight of rats in grams and age is in weeks.

• The y-intercept is 100 which means the rat is predicted to weigh about 100 grams at birth.

• The y-intercept is about 100, which means the rats gain about 100 grams a week.

• The y-intercept is 40 which means rats are predicted to weigh 40 grams at birth.

• The y-intercept is 40 which indicates that the rats grow about 40 grams per week.

Tags

CCSS.HSS.ID.C.7

Leslie cleans the barns for the horses. Her time spent cleaning can be modeled by the equation y = 15 x + 30, where x represents the number of stalls that contains horses. What is the meaning of the y-intercept?

• The time it takes to clean one horse

• the time it takes to clean one stall

• the time it takes to clean an empty barn

• the times it takes to clean each of the stalls with a horse

The equation y = -2x + 7 models the amount of gas remaining in a lawnmower after x hours of use since it was filled. What is the meaning of the slope?

• For each hour of mowing, the mower is predicted to use 2 gallons.

• the predicted amount of gas the lawnmower can hold is 2 gallons

• For every two hours of mowing, the mower is predicted to use 7 gallons.

• The predicted amount of gas remaining after 1 hour is 2 gallons.