Modeling Linear Data

What is a line of best fit used for?

• To make predictions

• To make the graph look pretty

• To connect the points

• To make it look like you know what you are doing

What type of correlation does this graph have?

• positive linear

• negative linear

• none

Which sentence describes the relationship shown on this scatter plot?

• As the temperature decreases, the visitors increase. 

• As the temperature increases, the number of visitors increases. 

• As the visitors increase, the temperature decreases. 

• No correlation

Is this line an accurate line estimate of best fit for the data?

• Yes

• No

What type of correlation does this graph have?

• positive linear

• negative linear

• none

Based on the graph, if Joe earned $400, how many hours did he work?

• 25 hours

• 35 hours

• 45 hours

• 15 hours

Residuals are . . . 

• possible models not explored by the researcher

• variation in the response variable that is explained by the model

• the difference between the y-values observed response and the y-values predicted by the model

• data collected from individuals that is not consistent with the rest of the group

If x is temperature and y is coffee sales, use the following formula to determine the coffee sales on a 34° day.

y = -60x+6443

• $4403

• $4673

• $8483

• $6443

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.

Rich is a member of a gym. He pays a monthly fee plus a per-visit fee. The equation below represents the monthly amount Rich pays for his membership to the gym per month for x visits. y= 10 + 3x What does the y-intercept of the graph of this equation represent?

• The monthly fee

• How much Rich pays per visit

• The number of times Rich goes to the gym

• The total cost at the end of the month