I assume you know how to enter data in your calculator. The keystrokes in the following pertain to TI92/92Plus/ Voyage 200 PLT. The main differences with the TI89/Ti89 Titanium is that the function keys F6,F7,F8 are not accessed directly but by the key sequences [2nd][F1], [2nd][F2], and [2nd][F3] respectively
1. CLEAN THE SLATE (so to speak) and ENTER DATA
In Home folder run F6: NewProb to reset the configuration.
Press Apps, and select 6: data/Matrix editor. Select a new data set
Give it a name: here testing.
Press OK/ENTER, The data entry screen opens, enter your values.
When you finish press F2.PlotSetUp.
2. Statistical plot setup and scatter plot drawing
Press F1:define to configure Plot1. Choose Scatter, then choose a mark for the data point. I select 5:Dot. and press [ENTER
Select the data column X=c1, Y=c2
ENTER to save configuration. Press [CTRL] [GRAPH] On my TI92 the CTRL
key is the [Diamond] key. On the following graph I changed the mark to a
cross to see the data point better. I also played with the window
dimension. You can also do that with ZoomStat. The graph remind me of a
parabola (I know I chose the exact values)
3. STATISTICAL CALC. AND REGRESSION ANALYSES.
Now we have to find the equation that fits these data best.
press APPS 6:Data/ Matrix editor but you select current to return to
your data set. You are taken to the data entry editor (Figure 3 above).
In that screen Press F5:Calc to edit the type of statistics you want
first line select the type of regression model : Linear Regression, QuadReg quadratic regression (or anything else available) X is from column1, Y is
from column 2. Store RegEQ The regression equation in say Y1(x)
Press ENTER to save to get the Regression Equation. Here it is
As you can see I cheated: a perfect parabola. R^2 =1.
And here the best fit represented on same graph as the statistical data
Usually you have to try different regression models, until you find the one that fits best the experimental data.