Getting the Standard Deviation from your calculator:
There are hundreds of calculators on the market that find the standard deviation. I have listed below the instructions on how to get the standard deviation from the calculators that I have in my office.
Current Calculators that I have in my office:
TI-83, TI-83Plus, TI-84,
TI-84Plus
If you do not have one of the calculators that I have listed below, you have several options.
Go to http://www.geocities.com/calculatorhelp/index.html . This site is not a university site and it is frequently
down, so be persistent.
Look at the manual for your calculator.
Go to Google and type “standard deviation with ‘insert your calculator name
here’ calculator”.
Example Data Set: 1, 1, 1, 4, 7, 7, 7 sample standard deviation = 3
Click on the Mode button twice until you see
“SD”. Select 1. This puts the calculator in Statistics Mode.
Enter the first number, 1.
Hit the M+. (n= 1 will appear in the window)
Enter the second number, 1.
Hit the M+ key.
(n=2 will appear in the window)
. . . .
.
Enter the last number, 7.
Hit the M+ key.
(n=7 will appear in the window)
Hit shift, 2. (This invokes the S-Var option.)
Hit 1 for the sample mean. Hit Enter.
Hit 3 for the sample standard deviation that we
will use in class. Hit Enter.
Enter the first number, 1.
Hit the Σ+ (Sigma+) key. ( n=1 will appear
in the window)
Enter the second number, 1.
Hit the Σ+ (Sigma+) key. (n=2 will appear in the window)
. . . .
.
Enter the last number, 7.
Hit the Σ+ (Sigma+) key. (n=7 will appear in the window)
Hit 2nd x2 (by hitting the
2nd key you are actually selecting the x-bar written above the key.)
This gives you the mean.
Hit 2nd sqrt(x).
This gives you the sample standard deviation which we will use in class.
Make sure you turn your calculator off and on
for new data sets.
Hit 2nd, Data (this means really that
you are entering the STAT menu)
Select 1-Var.
A blank screen will appear. Select Data again. X1
will appear.
Enter in 1. Scroll down, you will see FRQ=1.
Scroll down.
You will see X2=. Enter 1. Scroll
down, you will see FRQ=2. Scroll Down.
. . . .
Enter the last number 7. Scroll down, you will
see FRQ=7.
Select STATVAR.
Use the right arrow key to get: n, x-bar, and sx. If I ask you to compute the standard deviation
by hand, I am looking for sx— not
the other listed values.
Hit the 2nd and x<>y button.
(This puts us in Statistics 1 mode.)
Enter the first number, 1.
Hit the Σ+ (Sigma+) key. (1 will appear in
the window)
Enter the second number, 1.
Hit the Σ+ (Sigma+) key. (2 will appear in the window)
. . . .
.
Enter the last number, 7.
Hit the Σ+ (Sigma+) key. (7 will appear in the window)
Hit 2nd x2 (by hitting the
2nd key you are actually selecting the x-bar written above the key.)
This gives you the mean.
Hit 2nd sqrt(x).
This gives you the sample standard deviation which we will use in class.
Make sure you turn your calculator off and on
for new data sets.
Select STAT > Edit > Enter. List the data
down in column “L1”
When you are finished, select STAT> Calc>
1:1 Var Stats > Enter. It will return you back to
the mainscreen.
Select 2nd 1(you are actually
selecting L1). The number listed next to Sx is the
sample standard deviation.
TI-83,
TI-83 Plus, TI-84,
TI-84Plus
Hit 2nd and click on 0 (by hitting
the 2nd key you are actually selecting the catalog written above the
key.)
Select LN (You are actually selecting the S in
green.) This skips you through the catalog through the s’s.
Use the arrow down key at the top to scroll to stdDev( .
Hit Enter.
This will take you back to the main window.
Finish off the statement, so that it looks like this below.
stdDev({1,1,1,4,7,7,7})
Notice the insertion of the curly brackets. These are very important. After the above is entered, hit Enter.
Hit the Catalog key.
Select 3 (You are actually selecting the S in
purple.) This skips you through the catalog through to the s’s.
Use the arrow down key at the top to scroll to stdDev( .
Hit Enter.
This will take you back to the main window.
Finish off the statement, so that it looks like this below.
stdDev({1,1,1,4,7,7,7})
Notice the insertion of the curly brackets. These are very important. After the above is entered, hit Enter.