Linear Regression (9.2)

You are analyzing a scatter plot that has a negative correlation. What is true of the of the x and y values?

• As x increases, y decreases
• As x increases, y increases
• As x decreases, y decreases

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

The points in the scatterplot represent paired observations (x, y) where x is an individual’s weight and y is the time (in seconds) it takes for walking on a treadmill to raise the individual’s pulse rate to 140 beats per minute.  The open circles correspond to females and the dark squares to males.

• There is a positive correlation r between gender and weight, since men tend to weigh more than women.
• There is a negative correlation r between weight and time for both males and females.
• In general, males tend to take less time to have their pulse rate raised to 140 bpm while walking on the treadmill.

What type of correlation describes the following sentence:
The temperature outside and the number of hot chocolate sold at a football game.

• postive
• negative 
• no

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

CCSS.HSS.ID.C.9

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 line of best fit? 

• 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

What type of association does this graph have?

• positive 
• negative
• none
• all of the above

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

What type of association does this graph show?

• Positive
• negative
• none
• all of the above

Tags

CCSS.HSS.ID.B.6

If Joe worked 30 hours, how much is he expected to earn?

• $600
• $200
• $1000
• $800

Tags

CCSS.HSA.CED.A.1

CCSS.HSA.REI.B.3

CCSS.HSA.SSE.A.1

CCSS.HSF.BF.A.1

CCSS.HSF.IF.B.4

CCSS.HSF.LE.A.1

CCSS.HSF.LE.A.2

A correlation shows that two things are

• related
• causing each other
• unrelated
• causation

Tags

CCSS.HSS.ID.C.8

CCSS.HSS.ID.C.9

Some data were collected on the weight of a male while laboratory rat for the first 25 weeks after its birth. The linear regression equation is 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. 

Which is the best description of the y - intercept for the linear regression equation of the rats: weight^ = 100 + 40(time)?

• The y-intercept is 100 which means the rat is predicted to weigh 100 grams at birth. 
• The y-intercept is 100, which is where the graph crosses the y-axis. 
• 100 is where the data starts on the y-axis.