Chapter 12: Linear Regression and Correlation
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58. Piece-rate systems are widely debated incentive payment plans. In a recent study of loan officer effectiveness, the following piece-rate system was examined:
| of goal reached | 100 | 120 | ||
| Incentive | n/a | with an additional added per percentage point from | with an additional added per percentage point from | with an additional added per percentage point from |
If a loan officer makes of his or her goal, write the linear function that applies based on the incentive plan table. In context, explain the
-intercept and slope.
Q.12.10
A specialty cleaning company charges an equipment fee and an hourly labor fee. A linear equation that expresses the total amount of the fee the company charges for each session is .
What are the independent and dependent variables?
Q.12.10
For a given line of best fit, you compute that r = 0 using n = 100 data points. Can the line be used for prediction? Why or why not?
Q.12.11
A specialty cleaning company charges an equipment fee and an hourly labor fee. A linear equation that expresses the total amount of the fee the company charges for each session is .
What is the y-intercept and what is the slope? Interpret them using complete sentences
Q.12.13
Due to erosion, a river shoreline is losing several thousand pounds of soil each year. A linear equation that expresses the total amount of soil lost per year is .
How many pounds of soil does the shoreline lose in a year?
Q.12.14
Due to erosion, a river shoreline is losing several thousand pounds of soil each year. A linear equation that expresses the total amount of soil lost per year is .
What is the y-intercept? Interpret its meaning.
Q.12.15
The price of a single issue of stock can fluctuate throughout the day. A linear equation that represents the price of stock for Shipment Express is where x is the number of hours passed in an eight-hour day of trading.
What are the slope and y-intercept? Interpret their meaning.
Q.12.3
Emma’s Extreme Sports hires hang-gliding instructors and pays them a fee of per class as well as per student in the class. The total cost Emma pays depends on the number of students in a class. Find the equation that expresses the total cost in terms of the number of students in a class.
Q. 12. 5
Amelia plays basketball for her high school. She wants to improve to play at the college level. She notices that the number of points she scores in a game goes up in response to the number of hours she practices her jump shot each week. She records the following data:
| (hours practicing jump shot) | (points scored in a game) |
| 5 | 15 |
| 7 | 22 |
| 9 | 28 |
| 10 | 31 |
| 11 | 33 |
| 12 | 36 |
Construct a scatter plot and state if what Amelia thinks appears to be true.
Q.12.5
Amelia plays basketball for her high school. She wants to improve to play at the college level. She notices that the number of points she scores in a game goes up in response to the number of hours she practices her jump shot each week. She records the following data:
| X (hours practicing jump shot) | Y (points scored in a game) |
| 5 | 15 |
| 7 | 22 |
| 9 | 28 |
| 10 | 31 |
| 11 | 33 |
| 12 | 36 |