Math 131 Using the Stat Package on the TI89 24 Aug.
A. Clear the calculator (if necessary).
1. Go to MODE menu:
2. Press [MODE] [] [ENTER] this will put the calculator into graph function mode.
B. Enter two variable data into the calculator. See the TI89 Manual, Chapters 15 & 16.
1. Enter "Data/Matrix Editor": Press [APPS] [6:Data/Matrix Editor] [3:New]
2. "Data" should be blinking. Press. [] [] to get to the "variable" box.
3. Type "cell" (the name of the file) into this box: [2nd] [alpha] [c] [e] [l] [l] [alpha] [ENTER]
[ENTER] The data table should now appear on your screen.
4. A shaded cell should appear in the 1-row c1-column. The "x-values (the years)" will go in the
c1-column. Let 1990 be 0, 1991 be 1 etc. Enter the 0,1,2 etc. into c1-column by typing each
number followed by [ENTER].
5. When you have entered all the “x” values, press [] [] [] to access the top of the c2-
column. Then enter your y-values (subscribers) in the c2-column.
C. Graph data from the points you have entered.
1. At the top of the screen you will see "F2 Plot Setup". Press [F2] then [F1] to select "Plot 1"
to store the data for graphing.
2. The screen now shows various options for plotting.
3. "Plot Type 'scatter'" is already displayed so select it by pressing [].
Choose "Mark type 'cross'" by pressing [] [2] [].
4. Type "c1" into the x-box [alpha] [c] [1], then [] and "c2" into the y-box [alpha] [c] [2].
This lets the calculator know what set of values you wish to use for plotting.
5. Next press [ENTER] [] [Y=] to view the graphing screen. Note that "Plot 1" contains the
information you have set up.
6. Highlight "Plot 1" by moving the [] or [] button as needed.
7. Press [F2:Zoom] [9:ZoomData]. The graph of your data points should appear.
D. Calculate a regression equation for the points you have entered.
1. Enter [APPS] [6:Data/Matrix Editor] [1:Current]. This brings back the data table screen.
2. Press [F5] to set up the "Calculations" screen.
3. To set the calculation type to "ExpReg" (exponential regression), press the following: []
[4:ExpReg] []
4. Now enter "c1" into the x-box, [alpha] [c] [1] [] and "c2" into the y-box, [alpha] [c] [2] []
as before.
5. Next store the regression equation "RegEQ" in "y1" by pressing [] [] [ENTER]
6. Then press [] [] [ENTER] to display the regression line data.
E. Plot the regression equation.
1. Press [ENTER] [] [Y=] "y1" has been selected (the place where the regression equation has
been stored). (There should be a in front of "y1" showing that it has been selected.)
2. Press [F2:Zoom] [9:ZoomData]. The regression curve should appear on the same graph as
the points of the scatter plot.