Texas Instruments TI-84 Plus Silver Edition

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Finding a Linear Regression Model
Finding a Linear Regression ModelFinding a Linear Regression Model
Finding a Linear Regression Model
Enter the data from the table of values into L1 and L2 . Press STAT , CALC , LinReg, ENTER.
The top line gives the form of the equation. The next two lines give the values for a and b.
When writing down the linear regression model, round to four decimal places. (The last line
(
2
r
) gives a measure of the fit of the model to the data. The closer the number is to 1, the better
the model fits the data.)
On models of TI graphing calculators other than the TI-84, it may be necessary to press STAT ,
CALC , LinReg, ENTER, ENTER to find a linear regression.
Note, if
2
r
is not displayed, enable the Diagnostic feature of the calculator by pressing 2
nd
0 to
access the CATALOG . Then press
1
x
−
to enter the letter D. (The calculator is expecting a
letter entry while in the catalog, so ALPHA is not needed before pressing
1
x
−
.) Arrow down so
that DiagnosticON is on the display. Press ENTER, ENTER . The display screen should read
Done .
Example: Using the data given in the example above under Using Lists and Scatter
Plots, press STAT, CALC, LinReg, ENTER .
L1 and L2 STAT cursor over to CALC
LinReg ENTER
The linear regression model is
0.7692 2.8205
y x
= +
with an
2
r
value of 0.71.