Mean and Standard Deviation on a TI82 or TI83
Here's how to compute some basic statistics on your TI82. The TI83
works almost exactly the same. TI83
differences
are summarized here.

Press the [STAT] button. You should see this on your
screen:

Notice that EDIT and 1: are highlighted. Press [1]
or just [ENTER] to indicate you want to edit (i.e.
enter)
a list of numbers. Now your screen should look something like:
or:

If there is a list of numbers in the first column, as in the first
picture
above, press [DEL] until the column is empty, as in
the
second picture above.

Now type in your list of numbers, pressing [ENTER]after
each one. For instance, if your list of numbers is {1,3,4,5,7},
then when you are done, your screen should look like the first picture
in step #2 above. [Note: You do not have to enter the numbers
in
order]

Check over your list and make sure you have typed it correctly. You can
delete entries with the [DEL] key, or insert entries
by
using the [2nd][INS] keys. Note: To type [2nd][INS],
press the [2nd] key, then find INS above
the [DEL] key, and press that key.

Press the [STAT] button again, so that you are back
to:

Press the
key to highlight the CALC heading, and the screen
changes
to:

Notice that CALC and 1: are highlighted. Press [1]
or just [ENTER] to indicate you want to calculate
some onevariable statistics for your list. The screen now
looks
like:

Now tell the calculator what list you put your numbers in. Normally
this
will be the list L1, but use whatever list you typed
your
numbers under in step #4. To type L1, press [2nd][L1]
(L1 is over the [1] button). You
should
now see:

Press [ENTER]to do the computation:
The =4
tells you the mean of your list is 4. The x=2
tells
you the [population] standard deviation of your list is 2.
Short summary:
Press [STAT] and select EDIT to enter your
list
of numbers. Remember the list you entered them in (watch the heading
over
your number on the calculator screen). Press [STAT]
and
select CALC, then select 1Var Stats. Enter the name of the
list
you used, and press [ENTER] to view the results.
Test yourself:
Try to get the mean and standard deviation of 37.75, 38,
37,
38.5, and 37.5. You should get a mean of 37.75 and a standard deviation
of 0.5.
Bonus Topics:
Frequency tables:
If you have many repeated data items, such as a frequency table:
data item 
frequency 
3

4

8

5

1

7

5

1

...meaning that your list contains four 3's, five 8's, etc., then
you
can enter two lists of data (preferably in L1 and L2)
as shown:
Then ask the calculator to calculate 1variable statistics for L1
and L2 as shown:
Help with medians:
Once you type a list of numbers into a column in the list editor (see
steps
#1 #4 above), you can press [STAT] again, select
SortA(,
indicate L1 (or whatever list you put your numbers in)
and press enter: .
Then when you edit the list again, you will find the list is displayed
in ascending order, making it easier to pick out the median.
TI83 differences
First, several of the menus have additional options on the '83.
Second, the rightarrow button is curved and blue :)
Finally, the only important difference: If you do onevariable
statistics
and scroll down a bit on the results, you get a few bonuses  try it!
Last Modified February 2, 1999.
Prof.
Janeba's Home Page  Send comments or questions to: mjanebawillamette.edu
Department
of Mathematics  Willamette
University Home Page