Download Model data using Lines of Regression

Model data using Lines of
Regression
Why?
To predict and make
decisions and critical
judgements from a given set
of data.
Vocabulary
 Correlation
– Co (Together) or
relation
 Positive Correlation
 Negative Correlation
 No Correlation
 Line of best fit
 Regression Line
 Correlation coefficient (r)
Positive Correlation – slope is positive
and the points are close to the line
Negative Correlation – slope is negative and
the points are not close to the line
No correlation
Line of best fit – a line that closely
approximates a set of data
Regression Line
 Linear
regression consists of finding the
best-fitting straight line through the points.
The best fitting line is called the regression
line.
Correlation coefficient (r )
A
measure of how well data is modeled
by a linear equation
 When r is close to -1, the data has a
negative correlation
 When r=0, the data has no correlation
 When r is close to 1, the data has a
positive correlation
Types of Regression
 Linear



Quadratic
Exponential
Square Root.
Using the Calculator
 1.






Clear the memory
2nd
+
7
Move the cursor to ALL
Press Enter
2
Using the Calculator
 2.





Turn Diagnostic ON
2nd
0
Scroll down to DiagnosticON
Enter
Enter again
Using the Calculator
 3.




Turn statplot on
2nd
y=
Enter
Enter
Using the Calculator
 4.




Enter the data
STAT
1
Enter all x values in L1
Enter all y values in L2
Using the Calculator
 5.

Find the regression equation
Linear Equations
 STAT
 Move
the cursor right to CALC
 4 (Linreg)



a = slope
b = y intercept
r = correlation coefficient
Using the Calculator
 For

Same as before, but select 5 for Quadreg.
 For

Quadradic Equations:
Exponential Equations:
Same as before, but select 0 for Expreg.
Got it?
 Piece
of cake 
 Now
let’s do a couple of example
problems together.
 (Please
participate as this will be tested
and I don’t want to see everyone fail
again  )– No cell phones!!!
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