1. Analyzing Data
Standard Deviation

2. Standard Deviation
Range: The difference between the greatest and least values
Standard Deviation: Measure the variation in the data
***Small standard deviation (compared to data) indicates the data are clustered tightly around the mean
A large standard deviation may signify that the results of an experiment are inconclusive.

3. Measures of Central Tendency
Find the mean, median, and mode of the following data:
80, 82, 85, 90, 74, 75, 79, 79, 76

4. Using the Standard Deviation
Using the last example, within how many standard deviations of the mean do all the data values fall? 4

5. Finding Standard Deviation
Find the mean of the data set:
Find the difference between each value and the mean:
Square each difference:
Find the average of these squares:
Take the square root to find standard deviation:

6. Computing the Standard Deviation
Given data: 2, 3,4 6, 7, 9 10, 12, 13,14
Find the mean. 𝑥 =
L2: “L1- 𝑥 “
L3: L3^2
2nd>LIST>MATH>5:Sum(L3)
Divide by n
Take sqrt.

7. Finding Standard Deviation with the Calculator
Find the mean and standard deviation of the data for daily energy demand in a small town during August: 7

8. Finding Standard Deviation with the Calculator
Find the mean and standard deviation of the data for daily energy demand in a small town during August:
Step 1: Enter data into L1
Step 2: Use the CALC menu of STAT to access the 1-Var Stats option 8

9. 12.3 Analyzing Data 12.4 Standard Deviation 12.3 #3, 4-7, 10, 11, 13
12.4 #1-5, 8, 9, 15, 17-19 9