Mean and Standard Deviation on a TI-82/83/84
Here's how to compute some basic statistics on your TI-82, TI-83, and TI-84 (also the "plus" models, e.g. "TI-83 Plus"). TI-83 and TI-84
differences
are summarized here (there's are only few).
-
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:
- Now you can enter your data in the first column (or any other column you pick) just as you would in a computer spreadsheet.
If there is a list of numbers in the first column (or whatever column you want to use), as in the first
picture
above, put the cursor in that column, then 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 one-variable 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 1-Var 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 (exactly 0.5).
Bonus Topics:
Frequency tables:
If you have many repeated data items, such as a frequency table:
data item |
frequency |
3
|
4
|
4
|
5
|
1
|
7
|
5
|
1
|
...meaning that your list contains four 3's, five 4's, seven 1's etc., then
you
can enter two lists of data (preferably in L1 and L2)
as shown:
Then ask the calculator to calculate 1-variable statistics for L1
and L2 as shown:
Help with medians:
TI-82 ('83 is simpler, see below): 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.
TI-83/84: After you do the 1-Var Stats, just scroll down (with the down arrow) to see the median and some other statistics.
TI-83/4 differences
First, several of the menus have additional options on the '83.
Second, the right-arrow button is curved and blue :)
Finally, the only important difference: If you do one-variable
statistics
and scroll down a bit on the results, you get a few bonuses - try it!
Last Modified February 5, 2016.
Prof.
Janeba's Home Page | Send comments or questions to: mjanebawillamette.edu
Department
of Mathematics | Willamette
University Home Page