How To Do Statistics On The TI-89
The following applies to both the older TI-89 (hereafter referred to as the
TI-89) and the newer TI-89 Titanium (hereafter referred to as the Titanium). I
assume that you have the Stats/List Editor (SLE) installed. The SLE comes
preinstalled on the Titanium, and can be downloaded from the
Texas Instruments website for the older TI-89. You may have to upgrade
the calculator's OS first. Both of these activities will involve using the
cable you got with your calculator to connect it to a USB port on your
computer. The latest version of the OS for the TI-89 is 2.09, and for the
Titanium is 3.10. To check your OS version, from the Home screen press F1 and
then choose About from the dropdown menu. To check to see if the SLE is
installed, go to the APPS FlashApps menu. (I have the APPS Desktop turned
off on my Titanium. If you don't, you'll have to make the appropriate
ajustments to these instructions. The Desktop can be turned off via the
MODE menu.)
I'll begin with some simple things you can do without the SLE. The
built-in Data/Matrix Editor is reached via the APPS menu, but I prefer to
avoid it because the print on the screen is so tiny I can hardly read it. So
I'll be working from the Home screen.
I prefer to store lists in the X, Y, and Z variables, as those are so
easily accessed and do not involve a lot of key pressing on the keyboard.
However, if you follow my example, you should be sure to erase these lists
via 2nd F6 Clear a-z, or via VAR-LINK, when you are done with them, or they
may interfere with other functions of your calculator in which the X, Y, and
Z variables are used.
Enter a Single List (from the Home Screen)
{10,15,9,8,12,5,16,9} STO> X ###note: curly braces define lists; name it anything you want
Descriptive Statistics on the List
2nd MATH Statistics mean(X)
2nd MATH Statistics variance(X)
2nd MATH Statistics stdDev(X)
2nd MATH Statistics median(X)
2nd MATH Statistics OneVar X
The last command appears not to do anything other than return the word
Done. To see the results, do this (and then break out a magnifying glass if
your eyes are anything like mine).
2nd MATH Statistics ShowStat
Here are a few more commands via the List submenu.
2nd MATH List min(X)
2nd MATH List max(X)
2nd MATH List sum(X)
Edit this last command on the Entry line to get:
sum(X)^2
sum(X^2)
These, in turn, can be pasted from History to Entry to get sum of squares.
sum(X^2) - (sum(X)^2)/8 ###note: 8 is number of values in the list
Plot Graphs (from Home)
Set MODE Graph to Function if necessary.
<> Y= ###note: I am using <> as the diamond key.
highlight Plot1 and press Enter
change Plot Type to Histogram or Box Plot
enter X in the x... box
press the down arrow twice (I'm not sure why but this seems to be necessary)
press Enter
press F2 9 (ZoomData) and the graph will be drawn
use F3 (Trace) to get summary info from the boxplot (min, Q1, Md, Q3, max)
2nd Quit or HOME returns you to the Home screen
Enter a Second List (from Home)
{5,1,6,4,3,10,1,5} STO> Y
Work With Both Lists Simultaneously
2nd MATH Statistics TwoVar X,Y
2nd MATH Statistics ShowStat
2nd MATH Statistics Regressions LinReg X,Y
2nd MATH Statistics ShowStat
<> Y=
highlight Plot1 and press Enter
change Plot Type to Scatter (if necessary)
enter X in the x... box
enter Y in the y... box
press the down arrow twice
press Enter
press F2 9 (ZoomData)
To add the regression line to the plot, put the regression equation in Y1 and
press <> Graph.
Using the Stats/List Editor
Rather than reinvent the wheel, I'll just give a couple brief examples and
then some links to other websites. The SLE works very much like the statistical
functions on the TI-83/84. If your instructor is using one of those calculators,
follow her instructions. The examples given here should be sufficient to teach
you what you have to do differently to accomplish the same thing on the TI-89.
I've been told to get the SLE to work properly that you have to go into MODE
and set Exact/Approx to APPROXIMATE. I don't know if this is really true. I've
never done otherwise. (I always do what I'm told!)
The SLE is accessed via the APPS FlashApps menu (or from the APPS Desktop if
you have it turned on). When you go there, you'll be asked to select or create
a folder for your statistical work. I just stick with Main. Then you'll be
presented with the list editor, where you can enter your data. If this page is
not displaying columns for list1, list2, list3, and list4, press F1 Setup Editor
and press Enter.
To enter data into a list, use the arrow keys to move the cursor to the list
you wish to populate with data. The dashed line shows the first free position in
a list, so highlight that and begin typing values. Into list1, type: 10 Enter 15
Enter 9 Enter 8 Enter 12 Enter 5 Enter 16 Enter 9 Enter. Then use the right
arrow key to move the cursor into list2, highlighting the dashed line again, and
type: 5 Enter 1 Enter 6 Enter 4 Enter 3 Enter 10 Enter 1 Enter 5 Enter. You have
just put the same lists we were using above
into the List Editor. X is now in list1, and Y is in list2.
Descriptive Statistics
F4 1-Var Stats
type list1 into the List: box (or fetch it via 2nd VAR-LINK)
press Enter (I just had to press it twice)
wait (the TI-89 is considerably slower at statistics than the TI-83/84 is)
find your magnifying glass to read the output screen
use the down arrow key to see even more stuff
press Enter to dismiss the output screen
F4 2-Var Stats
type list1 into the X List box and press down arrow
press 2nd VAR-LINK and arrow down to highlight list 2 and press Enter
(obviously either one of those methods is okay for entering list names)
press Enter twice
go make some toast while the calculator is busy (okay, it's not THAT slow!)
use down arrow or 2nd down arrow to see more stuff on the output screen
press Enter to dismiss the output screen
Hypothesis Tests
2nd F6
select T-Test from the dropdown menu (single-sample t-test)
select data as your data entry method (the default apparently) and press Enter
enter the null hypothesized value into the mu0: box and press down arrow
enter the list name into the List: box and press down arrow
leave Freq: set at 1 and press down arrow
choose the type of Alternnative Hyp(othesis): you want and press down arrow
press Enter to Calculate the result, which will appear shortly on the results screen
press Enter to dismiss this screen
2nd F6
select 2-SampTTest from the dropdown menu
select data as your data entry method
enter list1 into the List1: box and press down arrow
enter list2 into the List2: box and press down arrow
down arrow past the Freq: boxes, leaving them set at 1
choose the form of the Alternative Hyp(othesis) you want and press down arrow
choose whether you want the pooled or unpooled test
press Enter to see the results screen
press 2nd down arrow to see more of the results screen
press Enter to dismiss the results screen
2nd F6
select ANOVA
set Data Input Method to Data and press down arrow (DO NOT press Enter!)
set the number of groups you've entered data for in the List Editor
press Enter
enter the names of the lists into the boxes in the dialog box (by typing or via 2nd VAR-LINK)
don't press Enter until you are done entering list names, THEN press Enter (probably twice)
wait for it!
examine the results screen, using 2nd down arrow to see it all
press Enter to dismiss the results screen
notice all the lists that have been added to your List Editor (I don't know what those are)
2nd F6
select LinReg T-Test from the dropdown menu
enter list1 into the X List: box (if it's not already there) and press down arrow
ditto list2 into Y List: and press down arrow
arrow past Freq: leaving it set at 1
choose the form of Alternative Hyp(othesis): you want and press down arrow
determine where you want the regression equation stored or just accept none and press down arrow
press Enter to see the results screen
squint!
use 2nd down arrow to see more of the results screen
press Enter to dismiss the results screen
notice that the residuals have been placed into a list called resid in case you want them
Note: You do not need to create new lists in the List Editor to do these
tests. You can use the X and Y lists that you created at the Home screen. Just
enter those names into the List1: and List2: or X List: and Y List: boxes on
the dialog screen when you are setting up the tests. You can also copy those
lists into the List Editor if you want to edit them. Just highlight the name of
an empty list with the cursor and press X and Enter to copy the list in X into
a list on the List Editor screen.
Clearing Lists in the List Editor
arrow the cursor to highlight the name of the list you want to clear
press CLEAR and then press Enter
or press F1 Clear Editor (which will erase list names and everything)
press F1 Setup Editor and press Enter twice
notice that the default lists have returned along with your old data, which has not been cleared
I don't see any way to clear all lists as on the TI-83, so live with it
Hypothesis Test on Categorical Data (Chi-Square TOI)
go to the HOME screen
press APPS Data/Matrix Editor New
change Type: to Matrix
leave Folder: set at Main
for Variable, type X and press down arrow (if you're not using X for something else)
press ALPHA to turn off alpha lock while cursing under your breath
enter the dimensions of your table of observed frequencies, using down arrow to move the cursor
press Enter twice (who knows why?!)
type your observed frequencies into the matrix editor, pressing Enter after each value
press 2nd QUIT when you are done entering the OFs
press APPS FlashApps Stats/List Editor Enter (you may have to press Enter twice to select Main folder)
press 2nd F6 Chi2 2-way
type X into the Observed Mat: box
down arrow past everything else to Calculate and press Enter
ogle the results screen
press Enter to dismiss the results screen
clear the X variable when you're done with it so it doesn't screw you up later
Normal Distribution Problems
press F5
choose Normal Cdf
enter the lower bound into the Lower Value: box and press down arrow
enter the upper bound into the Upper Value: box and press down arrow
for the unit normal distribution (z-scores), leave mu at 0 and sigma at 1
for a normal distribution that is not the unit normal, enter values for mu and sigma
press Enter to see the results screen
press Enter to dismiss the results screen
To Exit SLE
press HOME
Links
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