(regression models)
Enter Data^{ (1)}
> press LIST and type ordered pairs in L1 and L2
(hint: to quickly clear an old list, go to the top and press CLEAR)
To look at a scatterplot

To find the model (equation)
> press 2^{nd} STAT, CALC
> press LinReg, QuadReg, or ExpReg... (for linear, quadratic, and exponential regression, respectively)
> press ENTER (assuming you used L1 and L2) (if you wish to use other lists, they must be specified))
Load the equation into the calculator for future use
> press Y=
(> CLEAR out the old equationsif you didn't do this initially)
> press 2^{nd} VARS (for variables), Statistics, EQ, RegEQ (for regression equation)
To see your model graphed on top of the scatterplot
> press GRAPH^{ (2)}
To plug in an xvalue into your model^{ (3)}
> 2^{nd} QUIT (to return to the home screen, if needed)
> press 2^{nd} VARS (for variables), YVars, Y1 (or whichever function you loaded it into), "(#)" where # is a number, ENTER
1. Before entering data, it is good practice to press Y= and CLEAR all existing equations.
2. TRACE works nicely at this point. steps x right and left. switches from the data to the model and back.
3. The other way to plug in an xvalue(s) is to use the Table, using TBLSET and TABLE.
Jim Olsen, Western Illinois University