1.5 Scatter Plots and Lines of Best Fit part 1.pdf · 27/09/2011 · 1.5 Scatter Plots and Lines...
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1 1.5 Scatter Plots and Lines of Best Fit Essential Questions: How can I use a scatter plot to draw informal inference about the correlation between two variables? How do I determine an equation for the line of best fit using a graphing calculator? In many realworld problems, you will find data that relate two variables such as time and distance or age and height. You can view the relationship between two variables with a scatter plot. A scatter plot is the graph of the ordered pairs that describe a relationship between two sets of data. 0 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 x y Correlation Positive correlation Negative correlation 6 5 4 3 2 1 0 1 2 3 4 5 6 6 5 4 3 2 1 1 2 3 4 5 6 x y 6 5 4 3 2 1 0 1 2 3 4 5 6 6 5 4 3 2 1 1 2 3 4 5 6 x y
Transcript of 1.5 Scatter Plots and Lines of Best Fit part 1.pdf · 27/09/2011 · 1.5 Scatter Plots and Lines...
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1.5 Scatter Plots and Lines of Best FitEssential Questions: How can I use ascatter plot to draw informal inferenceabout the correlation between twovariables? How do I determine an equationfor the line of best fit using a graphingcalculator?
In many realworld problems, youwill find data that relate twovariables such as time anddistance or age and height. Youcan view the relationship betweentwo variables with a scatter plot.
A scatter plot is the graph of the ordered pairs that describe
a relationship betweentwo sets of data.
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Correlation
Positive correlation Negative correlation
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Correlation continued
No correlation
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Let's collectsome data.
Name Age (in years)
Height(in inches)
Wingspan(in inches)
# of Letters in Last Name
Celina
Ally
Jajaun
Luke
Quad'gee
Sarah
Dede
Jordan
Taylor
Chanel
Lauren
Myeisha
Michael Ma.
Mike Mo.
Caitlyn
Nicolette
DeVante
Celia
Aaron
Jackie
Haimbach
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Line of Best Fit
A scatter plot can help you see patterns in data involving two variables. A line of best fit is a linear model that fits that data.
Part 1: Input the data from the table into your calculator:1) Stat2) Edit3) Input ages into L1, height into L2, wingspan into L3, and number of letters in last name in L4
Part 2: Make it so that you will be able to see the points on a graph:
1) 2nd2) Y =3) Go into the first stat plot4) Turn the stat plot on5) Make sure that L1 is used for x and L2 is used for y
Line of Best Fit continued
Part 3: View the graph:1) Window2) Find the minimum and maximum values for x from the table. Set appropriate values for the xmin, xmax, and xscl.3) Find the minimum and maximum values for y from the table,
and set appropriate values for the ymin, ymax, and yscl.4) Graph
Part 4: Write the line of best fit:1) Stat2) Calc3) 4: LinReg (ax + b) L2, L34) EnterThis gives you the equation for the line of best fit.
