Scatter PlotsBelow is a sample scatter plot, can you tell me what

they are designed to show.

ANSWER

• Scatter plots are most often used to show correlations or relationships among data.

Common Core #25-28

SCATTER PLOTS, VENN DIAGRAMS, TWO-WAY FREQUENCY TABLES

Scatter Plots Type #1

• POSITIVE

• STRONG or WEAK

As the number of hours that you study increases your overall class grade increases

Scatter Plots – Positive Correlation

Study Time Class Grade

0 55

0.5 61

1 67

1.5 73

2 81

2.5 89

3 91

3.5 93

4 95

4.5 97

How Study Time Affects Grades

0

20

40

60

80

100

120

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

Time in hours

Ove

rall

grad

e

Make a prediction for a study time of 5 hours.

Scatter Plot Type #2

• NEGATIVE

• STRONG or WEAK

The age of a person and amount of time spent playing video games.

Scatter Plots – Negative Correlation

Make a prediction a 5 year old? 80 year old?

Scatter Plots #3

• NONE

There is no relationship between the number of shirts someone owns and their annual salary

Scatter Plots – No CorrelationHow does your wardrobe affect your

salary

0

20

40

60

80

0 10 20 30 40 50

Number of shirts owned

Sala

ry

Can you make a prediction based on this data?

Line of Best Fit & Outliers

• A line of best fit is a line that best represents the data on a scatter plot and often shows a trend in the data.

• Outliers are points too far away from the line of best fit.

NAME THAT SCATTER PLOTWEAK POSITIVE

NAME THAT SCATTER PLOTNONE

NAME THAT SCATTER PLOTSTRONG POSITIVE

NAME THAT SCATTER PLOTSTRONG NEGATIVE

Practice Problems

Pages 388-389

3-5, 11-12