1. 1-8 Scatter Plots Warm Up Problem of the Day Lesson Presentation
Course 2

2. Course 2
1-8
Scatter Plots
Warm Up
Which of the following pairs do you think have a cause-and-effect relationship?
1. height and age
2. hand span and address
3. grade average and shoe size
4. temperature and date
yes no no
yes

3. 1-8 Scatter Plots Problem of the Day
Course 2
1-8
Scatter Plots
Problem of the Day
From the pizza shop, James walks 12 blocks south, 22 blocks east, 18 blocks north, and 30 blocks west. James realizes that he left his wallet at the pizza shop. What is the least number of blocks James must walk to return to the pizza shop?
14 blocks

4. 1-8 Scatter Plots Learn to display and analyze data in scatter plots.
Course 2
1-8
Scatter Plots
Learn to display and analyze data in scatter plots.

5. Vocabulary 1-8 Scatter Plots scatter plot positive correlation
Course 2
1-8
Scatter Plots
Vocabulary
scatter plot
positive correlation
negative correlation
no correlation

6. Course 2
1-8
Scatter Plots
To find out if two sets of data may be related, you can make a scatter plot of the data values in each set.
A scatter plot has two number lines, called axes—one for each set of data values.
Each point on the scatter plot represents a pair of data values. These points may appear to be scattered or may cluster in the shape of a line or a curve.

7. 1-8 Scatter Plots Additional Example 1: Making a Scatter Plot
Course 2
1-8
Scatter Plots
Additional Example 1: Making a Scatter Plot
Use the data to make a scatter plot. Describe the relationship between the data sets.
300
240
180
120 60
Type U.S. Only Rest of World
Mammals
Birds
Reptiles
Amphibians
Fishes
Clams
Number of Endangered Species
Step 1: Determine the scale and interval for each axis. Place the number of animals endangered in the U.S. on the horizontal axis and the number of animals endangered in the rest of the world on the vertical axis.

8. 1-8 Scatter Plots Additional Example 1 Continued
Course 2
1-8
Scatter Plots
Additional Example 1 Continued
300
240
180
120 60
Type U.S. Only Rest of World
Mammals
Birds
Reptiles
Amphibians
Fishes
Clams
Number of Endangered Species
Step 2: Plot a point for each pair of values.

9. 1-8 Scatter Plots Additional Example 1 Continued
Course 2
1-8
Scatter Plots
Additional Example 1 Continued
Use the data to make a scatter plot. Describe the relationship between the data sets.
Number of Endangered Species
300
240
180
120 60
Type U.S. Only Rest of World
Mammals
Birds
Reptiles
Amphibians
Fishes
Clams
Number of Endangered Species
Rest of World
U.S.
Step 3: Label the axes and give the graph a title.

10. 1-8 Scatter Plots Additional Example 1 Continued
Course 2
1-8
Scatter Plots
Additional Example 1 Continued
Use the data to make a scatter plot. Describe the relationship between the data sets.
Number of Endangered Species
300
240
180
120 60
Type U.S. Only Rest of World
Mammals
Birds
Reptiles
Amphibians
Fishes
Clams
Number of Endangered Species
Rest of World
U.S.
There appears to be no relationship between the data sets.

11. Number of farm workers in thousands
Course 2
1-8
Scatter Plots
Try This: Example 1
Use the data to make a scatter plot. Describe the relationship between the data sets.
10,000
8,000
6,000
4,000
2,000
,995
,858
,132
,881
,818
,864
Number of farm workers in thousands
Year
Step 1: Determine the scale and interval for each axis. Place the year on the horizontal axis and the number of farm workers on the vertical axis.

12. 1-8 Scatter Plots Try This: Example 1 Continued 1940 8,995 1950 6,858
Course 2
1-8
Scatter Plots
Try This: Example 1 Continued
10,000
8,000
6,000
4,000
2,000
,995
,858
,132
,881
,818
,864
Number of farm workers in thousands
Year
Step 2: Plot a point from each pair of values.

13. 1-8 Scatter Plots Try This: Example 1 Continued 1940 8,995 1950 6,858
Course 2
1-8
Scatter Plots
Try This: Example 1 Continued
Number of Farm Workers
10,000
8,000
6,000
4,000
2,000
,995
,858
,132
,881
,818
,864
Number of farm workers in thousands
Year
Number (in thousands)
Year
Step 3: Label the axes and give the graph a title.

14. 1-8 Scatter Plots Try This: Example 1 Continued 1940 8,995 1950 6,858
Course 2
1-8
Scatter Plots
Try This: Example 1 Continued
Number of Farm Workers
10,000
8,000
6,000
4,000
2,000
,995
,858
,132
,881
,818
,864
Number of farm workers in thousands
Year
Number (in thousands)
Year
The number of farm workers decreased from 1940 to 1970.

15. Course 2
1-8
Scatter Plots
There are three ways to describe data displayed in a scatter plot.
Positive Correlation
Negative Correlation
No Correlation
The values in both data sets increase at the same time.
The values in one data set increase as the values in the other set decrease.
The values in both data sets show no pattern.

16. Additional Example 2A: Determining Relationships Between Two Variables
Course 2
1-8
Scatter Plots
Additional Example 2A: Determining Relationships Between Two Variables
Write positive correlation, negative correlation, or no correlation to describe each relationship.
The graph shows that as area increases, population increases. So the graph shows a positive correlation between the data sets.

17. Additional Example 2B: Determining Relationships Between Two Variables
Course 2
1-8
Scatter Plots
Additional Example 2B: Determining Relationships Between Two Variables
Write positive correlation, negative correlation, or no correlation to describe each relationship.
The graph shows that as the year increases, sales decrease. So the graph shows a negative correlation between the data sets.

18. Additional Example 2C: Determining Relationships Between Two Variables
Course 2
1-8
Scatter Plots
Additional Example 2C: Determining Relationships Between Two Variables
Write positive correlation, negative correlation, or no correlation to describe each relationship.
height and number of vacation days
The number of vacation days is not related to height. So there would not be any correlation between these two variables.

19. 1-8 Scatter Plots Try This: Example 2A
Course 2
1-8
Scatter Plots
Try This: Example 2A
Write positive correlation, negative correlation, or no correlation to describe each relationship.
The graph shows that as the year increases, number of tornados increases. So the graph shows a positive correlation between the data sets.

20. 1-8 Scatter Plots Try This: Example 2B
Course 2
1-8
Scatter Plots
Try This: Example 2B
Write positive correlation, negative correlation, or no correlation to describe each relationship.
The graph shows that as the length of string increases, frequency decreases. So the graph shows a negative correlation between the data sets.
vps = vibrations per second

21. 1-8 Scatter Plots Try This: Example 2C eye color and age
Course 2
1-8
Scatter Plots
Try This: Example 2C
Write positive correlation, negative correlation, or no correlation to describe each relationship.
eye color and age
There would not be any correlation between these two variables.

22. 1-8 Scatter Plots Lesson Quiz: Part 1
Course 2
1-8
Scatter Plots
Lesson Quiz: Part 1
1. The table shows the daily attendance at the beach. Use the data to make a scatter plot of the data and describe the relationship between the data sets.
Temperature Attendance
The graph shows a positive correlation.

23. 1-8 Scatter Plots Lesson Quiz: Part 2
Course 2
1-8
Scatter Plots
Lesson Quiz: Part 2
2. Write positive, negative, or no correlation to describe the relationship shown.
negative correlation