**Getting the Standard
Deviation from your calculator:**

I have used the following data set to get the mean with several different calculators.

1, 1, 1, 4, 7, 7, 7 standard deviation = 3

Current Calculators that I have in my office:

There are hundreds of calculators on the market that find the standard deviation. If you do not have one of these calculators, you have several options.

- Look at the manual for your calculator.
- Go to Google and type “standard deviation with __________ calculator”.

- 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.

- · MODE button
- · 3 for STAT
- · 1 for 1-VAR
- · Enter your data 1, enter, 1, enter, etc
- · SHIFT 1 for [STAT]
- · 5 for Var
- · 3 for population standard deviation or 4 for sample
standard deviation. Also, 2 for mean.

**TI-30Xa**

- 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 2
^{nd}x^{2}(by hitting the 2^{nd}key you are actually selecting the x-bar written above the key.) This gives you the mean. - Hit 2
^{nd}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 2
^{nd}, Data (this means really that you are entering the STAT menu) - Select 1-Var.
- A blank screen will appear. Select Data again. X
_{1}will appear. - Enter in 1. Scroll down, you will see FRQ=1. Scroll down.
- You will see X
_{2}=. 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 s
_{x}. If I ask you to compute the standard deviation by hand, I am looking for s_{x— }not the other listed values.

- Hit the 2
^{nd}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 2
^{nd}x^{2}(by hitting the 2^{nd}key you are actually selecting the x-bar written above the key.) This gives you the mean. - Hit 2
^{nd}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.

**TI-83, TI-83 Plus **

- Hit 2
^{nd}and click on 0 (by hitting the 2^{nd}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 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.