1. Warm Up What is the mean, median, mode and outlier of the following data: 16, 19, 21, 18, 18, 54, 20, 22, 23, 17
Mean: 22.8
Median: 19.5
Mode: 18
Outlier: 54

2. 11-6 Analyzing Data Objective:
I can describe and compare data sets using various statistical measures.

3. Statistical Measures Mean ( 𝑥 ): Median: Mode: Outlier:
Sum of data values Number of data values
Also known as
“Measures of Central Tendency”
Median:
Middle value of an ordered data set
Even number: average the two middle values.
Mode:
Data value that occurs most often.
Outlier:
Data value substantially different from rest of data
Range of a data set:
Maximum Value – Minimum Value
Percentile:
Percent of data less than or equal to chosen value.
# of values ≤given value Total # of values

4. Objective: I can find and apply the standard deviation for a data set.

5. Standard Deviation Variance: average of deviation squared 𝜎 2 =2
Distance from mean
Variance:
average of deviation squared
Data
182
186
184
185
Deviation
(Deviation)2
𝜎 2 = (𝑥− 𝑥 ) 2 𝑛
− 2 4
 (measures how far a set of (random) numbers are spread out from their mean) 2 4
𝜎 2 =2
− 2 4
Standard Deviation:
Square root of variance 1 1
(𝑥− 𝑥 ) 2 𝑛 𝜎=
=1.41 1 1
Mean:

6. Using standard deviation to describe data
Number of hurricanes in Atlantic Ocean from 1992 to 2006
Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 #
W.S. Calculating Standard Deviation
Find the mean, variance and standard deviation for the number of hurricanes.
Create a dot plot of the hurricanes.
mean:
7.26
Variation:
10.30
standard deviation
3.21
mean
3.21
3.21
3.21
3.21
3.21
3.21 3 2
Data falls within ___ standard deviations of the mean. 1 ?