Calculator Strokes for Regression

TI-83 and 84

Data and Plots

1. Turn on a Stat Plot:

        2nd STAT PLOT (Y =)

ENTER (Selection 1)
ON (push ENTER to highlight ON)
Choose type of plot : First picture highlightes,  Scatter plot
2. Clear L1 (list 1) and L2 (list 2):
CLEAR
STAT
4 (ClrList)
L1 (2nd 1) and ENTER
Repeat but with L2 (2nd 2)
3. Enter data needed to be plotted:
STAT
1 (Edit)
Enter data into L1 and L2 using arrow keys
Exit from screen by pressing 2nd QUIT (MODE)
4. Plot data:
Make sure all plots in Y = are cleared
Adjust WINDOW to fit your data
Press GRAPH
Note: Before attempting to graph an equation later you MUST turn off your STAT PLOT: 
2nd STAT PLOT
1
Highlight OFF then press ENTER
QUIT

Regression Equations

1. After graphing your data decide if it looks

Linear: LinReg (ax + b)
Quadratic: QuadReg
Cubic: CubicReg
Quartic: QuartReg
Logarithmic: LnReg
Exponential: ExpReg
Logistic: Logistic
2. Press STAT, move with arrows to CALC, press the number of the regression you think fits your data, press ENTER.

3. The values are calculated automatically. To put these into a equation to graph press
        Y=

        VARS

        Statistics (5)

        Using the arrows move over to EQ

        Press 1 for RegEQ (regression equation)
 

You will see the official equation in Y1 and you may use this to calculate future values.

To graph this equations so you can see how it matches your data, press GRAPH.

You can change your choice of type of regression by returning to Y= , clearing the equation and going back to part (1) of this section and repeating steps 1 to 3.
 
 
 
 

P.Dueck, 1996