Investigating Scatter Plots Mr. J. D. Miles www.JovanMiles.com [email protected]
Transcript
Slide 1
Investigating Scatter Plots Mr. J. D. Miles www.JovanMiles.com
[email protected]
Slide 2
Investigating Scatter Plots
Slide 3
Scatter plots are similar to line graphs in that each graph
uses the horizontal ( x ) axis and vertical ( y ) axis to plot data
points. Scatter plots are most often used to show correlations or
relationships among data.
Slide 4
Investigating Scatter Plots Positive correlations occur when
two variables or values move in the same direction. As the number
of hours that you study increases your overall class grade
increases
Investigating Scatter Plots Negative Correlations occur when
variables move in opposite directions As the number of days per
month that you exercise increases your actual weight decreases
Investigating Scatter Plots No correlation exists if there is
no noticeable pattern in the data There is no relationship between
the number of shirts someone owns and their annual salary
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Investigating Scatter Plots No Correlation number of shirts
ownedsalary 11 20 350 430 525 617 72 840 98 1025 1112 7 1319 1455
1571 169
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Line of Best Fit A line of best fit is a line that best
represents the data on a scatter plot. A line of best fit may also
be called a trend line since it shows us the trend of the data The
line may pass through some of the points, none of the points, or
all of the points. The purpose of the line of best fit is to show
the overall trend or pattern in the data and to allow the reader to
make predictions about future trends in the data.
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Use the data to create a scatter plot Sandwich Total Fat (g)
(X) Total Calories (y) Hamburger9260 Cheeseburger13320 Quarter
Pounder21420 Quarter Pounder with Cheese30530 Big Mac31560 Arch
Sandwich Special31550 Arch Special with Bacon34590 Crispy
Chicken25500 Fish Fillet28560 Grilled Chicken20440 Grilled Chicken
Light5300
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Scatter Plot of the Data
Slide 13
Things to remember A scatter plot with a positive correlation
has X and Y values that rise together. A scatter plot with a
negative correlation has X values that rise as Y values decrease A
scatter plot with no correlation has no visible relationship The
line of best fit is the line that best shows the trend of the
data
Slide 14
Investigating Scatter Plots Mr. J. D. Miles www.JovanMiles.com
[email protected]