COPYING A MODEL

Rather than retyping each model back into your calculator, you can use this shortcut.

Ask the calculator to fit a model to the data. (Use STAT, CALC, etc.) Then go to the Y= editor, as if you intend to type in the function manually.

Once you see "y1=" on your screen-- and make sure you've cleared out any functions that are already entered there for y1, y2, etc.-- follow these steps:

On the TI-82/83: hit VARS, select Statistics, then Eq, then RegEq; your calculator will automatically type in the last model you found.

On the TI-85/86: go to CATALOG or CATLG-VARS (which is 2nd, CUSTOM), select ALL, then page down (using F1) until you see "RegEq" and select that. Your Y= editor now shows "y1=RegEq." If you graph that, you will see the model.