1. What type of
correlation does the following graph have?
|
A
|
positive
linear correlation
|
|
B
|
negative
linear correlation
|
|
C
|
no
correlation
|
|
D
|
nonlinear correlation
|
2. Which of the
following does not have negative
correlation?
|
A
|
number
of hours watching TV per week versus grade-point average
|
|
B
|
car
weight versus miles per gallon
|
|
C
|
height
versus weight
|
|
D
|
price of an item versus
number of people who want it
|
3. The scatter plot has what type of correlation?
|
A
|
nonlinear
correlation
|
|
B
|
no
correlation
|
|
C
|
negative
linear correlation
|
|
D
|
positive linear
correlation
|
4. The equation for
the line of best fit is written in what form?
|
A
|
slope-intercept
form
|
|
B
|
standard
form
|
|
C
|
point-slope
form
|
|
D
|
vertex form
|
5. In the Stroop
Lab, what does the slope represent?
|
A
|
number
of words in the list
|
|
B
|
color
of the word
|
|
C
|
number
of correct matches
|
|
D
|
seconds per word
|
6. Which equation
best represents the line of best fit for the following scatter plot?
|
A
|
y = x + 50
|
|
B
|
y = −50x + 1
|
|
C
|
y = −x + 50
|
|
D
|
y = x – 50
|
7. Equations of
lines of best fit are used for what?
|
A
|
to
tell stories
|
|
B
|
to
make predictions
|
|
C
|
to
draw graphs
|
|
D
|
to prove correlation
|
8. The line of best
fit for time versus the cost of a gallon of milk is y = .02x + .10 where x represents the number of years after
1930 and y represents cost. What was
the cost of a gallon of milk in 1970?
|
A
|
$0.90
|
|
B
|
$39.50
|
|
C
|
$1.50
|
|
D
|
$4.80
|
9. The line of best
fit for time versus the cost of a gallon of milk is y = .02x + .10 where x represents the number of years after
1930 and y represents cost. In what
year was milk $1.20 per gallon?
|
A
|
1940
|
|
B
|
1955
|
|
C
|
1985
|
|
D
|
1995
|
Multiple-Choice Answer Key
|
1. A
|
2. C
|
3. B
|
4. A
|
5. D
|
|
6. C
|
7. B
|
8. A
|
9. C
|
|
Short-Answer Items:
10. Graph a scatter
plot that has a negative correlation.
11. The line of best
fit is drawn in the scatter plot. What is the equation of the line of best fit?
12. Plot the
following data, draw a line of best fit, and write the equation of the line of
best fit.
|
x
|
0
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
10
|
|
y
|
2
|
5
|
9
|
10
|
14
|
19
|
21
|
25
|
30
|
Short-Answer Key and Scoring
Rubrics:
10. Graph a scatter
plot that has a negative correlation.
Answers will vary.
11. The line of best
fit is drawn in the scatter plot. What is the equation of the line of best fit?
y = (7/6)x
12. Plot the
following data, draw a line of best fit, and write the equation of the line of
best fit.
|
x
|
0
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
10
|
|
y
|
2
|
5
|
9
|
10
|
14
|
19
|
21
|
25
|
30
|
y = 2.954x + 2.528 (from
calc)
|
Points
|
Description
|
|
3
|
·
An accurate line of best fit has been drawn on
a scatter plot with axes labeled.
·
An accurate equation for the line of best fit
has been provided.
|
|
2
|
·
The scatter plot is made and there is a line
of best fit but no equation.
|
|
1
|
·
The line of best fit equation is provided, but
there is no scatter plot or line of best fit drawn.
|
|
0
|
·
The student’s response is incorrect,
irrelevant, too brief to evaluate, or missing.
|
Performance Assessment:
Research and find two variables that have linear correlation.
1. Make a table
of values with your data.
2. Make a scatter
plot of your data and label the axes.
3. Draw in a
line of best fit.
4. Write the
equation of the line of best fit:
5. What does the
slope represent in terms of your data?
6. What does the
y-intercept represent in terms of
your data?
7. Using your line
of best fit, write one question in which you have to solve for y. Show the answer.
8. Using your line
of best fit, write one question in which you have to solve for x. Show the answer.
Performance Assessment Scoring Rubric:
|
Points
|
Description
|
|
5
|
The student has the following:
·
a table with data that correlates linearly
·
a scatter plot with axes labeled
·
a graph of the line of best fit
·
the equation of the line of best fit
·
a proper explanation of the slope
·
a proper explanation of the y-intercept
·
one question and answer in which solving for y
·
one question and answer in which solving for x
|
|
4
|
The student has the following:
·
a table with data that correlates linearly
·
a scatter plot, but axes are not labeled
·
a graph of the line of best fit
·
the equation of the line of best fit
·
a proper explanation of the slope
·
a proper explanation of the y-intercept
·
one question and answer in which solving for y
·
one question and answer in which solving for x
|
|
3
|
The student has the following:
·
a table with data that correlates linearly
·
a scatter plot, but axes are not labeled
·
the equation of the line of best fit, but not
its graph
·
a proper explanation of the slope
·
a proper explanation of the y-intercept
·
one question and answer in which solving for y
·
one question and answer in which solving for x
|
|
2
|
The student has the following:
·
a table with data that correlates linearly
·
the equation of the line of best fit
·
incorrect explanations of slope and y-intercept
·
one question and answer in which solving for y
·
one question and answer in which solving for x
|
|
1
|
The student has the following:
·
a table with data that correlates linearly
·
the equation of the line of best fit
·
incorrect explanations of slope and y-intercept
·
one question but missing the answer in which
solving for y
·
one question but missing the answer in which
solving for x
|
|
0
|
The student’s response is incorrect, irrelevant, too brief to
evaluate, or missing.
|
