# A11­5ScatterPlots.notebook February 17, 2015 Algebra 1 Ch.6 Notes Page 32

```A11&shy;5ScatterPlots.notebook
Algebra 1
Ch.6 Notes Page 32
P32 1&shy;5 Scatter Plots
February 17, 2015
Scatter Plots are...
Relationships between two sets of data.
Both Data Sets Go
Up/Down Together
One Goes Up the
Other Goes Down
Sep 2&shy;8:31 AM
Data is not Related
Jan 5&shy;3:12 PM
Make two Scatter Plots on the same graph.
The Scatter Plot below shows data collected from students about the score they earned on a test verses how many hours they watched television the pervious day.
Jan 5&shy;3:12 PM
Year 1950 1960 1970 1980 1990 2000 Newspaper Circulation 54 (Millions)
59 62 62 62 55 Homes with 4 Televisions
(Millions)
46 59 76 92 101
Jan 5&shy;3:12 PM
1
A11&shy;5ScatterPlots.notebook
February 17, 2015
Example
Trend Lines (Lines of Best Fit)
Shows a correlation.
About 1/2 of the points should be above
and 1/2 of the points should be below the line.
A Trend Line (or Line of Best Fit) also shows
relative Strong or Weak Correlations.
Jan 5&shy;3:12 PM
A scatter plot shows the age and asking price of several used mid&shy;sized cars. What type of correlation does the scatter plot show?
a) Negative Correlation
c) Undefined Correlation
b) No Correlation
d) Positive Correlation
Jan 5&shy;3:13 PM
Scatter Plot Data
Graphing Calculators
\$
10
11
9
10
13
5
8
4
Gallons
6.3
6.1
5.6
5.5
8.3
2.9
5.2
2.7
Price
21
28
36
40
# Sold
130
112
82
65
Oct 13&shy;3:07 PM
Age
3
5
8
11
12
10
4
9
6
7
11
Height
36
40
45
56
64
52
37
51
42
44
60
Oct 13&shy;3:08 PM
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A11&shy;5ScatterPlots.notebook
Correlation does NOT mean Cause
February 17, 2015
In Class (Tomorrow)
1&shy;5 P35 #1&shy;11,16,18&shy;20
If a change in one quantity causes a change in a second quantity, then the quantities have a causal relationship.
Please put your name and class period at the top of the homework.
Also include the homework number.
Quantities can be correlated but not have a causal relationship.
One thing does not have to cause another in order for them to be correlated.
Oct 14&shy;7:57 AM
Oct 13&shy;3:08 PM
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