Regression Assignment

The correlation coefficient is represented by the letter _______.

• r
• r^2

• m

• b

Analyze the correlation coefficient of r=0.85 in the context of two variables, age and salary. What does this suggest about the relationship between these variables?

• There is a strong positive correlation between age and salary.
• Salary decreases as age increases.
• There is no correlation between age and salary.
• Age has a negative impact on salary.

Match the following

• weak negative correlation

• -0.97

• strong negative correlation

• -0.44

• weak positive correlation

• +0.31

• strong positive correlation

• +0.99

Tags

CCSS.6.NS.C.5

CCSS.6.NS.C.6

A perfectly negative correlation 

• implies a coefficient of determination of –1.0. 
• means that there must be a slope of –1.0.
• says that for every one additional unit of the variable on the x–axis, the variable on the y–axismust move down one additional unit.
• means that the r–value is is exactly 1.0. 

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

Which situation describes a negative correlation?

• the amount of time spent on your phone and the battery left on the phone

• the number of hours spent studying and the test score

• the number of miles driven and the amount of gas used

• hair color and intelligence

James is studying how temperature affects the drying time of concrete. He records the following data:

Temperature (x) (°F), Drying Time (y) (hours)

50 24

60 20

70 18

80 15

90 12

1. Find the equation of the line of best fit for the data.
   

• y = -0.29x + 38.1

• y = 38.1x - 0.29

• y = 38.1x + 0.9917

• y = -0.29x - 0.9959

James is studying how temperature affects the drying time of concrete.

y=-0.29x+38.1

interpret the slope.

1. 
   

• The slope of -0.29 indicates that for each 1 degree increase in temperature, the drying time decreases by 0.29 units.
• The slope of -0.29 suggests that a decrease in temperature leads to a decrease in drying time by 0.29 units.
• The slope of -0.29 indicates that the drying time is constant regardless of temperature changes.
• The slope of -0.29 means that for each 1 degree increase in temperature, the drying time increases by 0.29 units.

James is studying how temperature affects the drying time of concrete.

y=-0.29x+38.1

Predict the drying time at 75°F using the regression equation.

1. 
   

• 16.35
• 25.0
• 12.75
• 20.5

James is studying how temperature affects the drying time of concrete.

y=-0.29x+38.1

What is the drying time when the temperature is 100°F?

1. 
   

• 5.3 hours
• 9.1 hours
• 12.7 hours
• 15.0 hours