Frequency Distribution
Table
Percentile
The pth percentile of a distribution
is the value such that p percent of
the observation fall at or below it.
Standardized test scores
Roberto received his ACT score
and it says he’s in the 80th
percentile. What does that mean?
80% of the people who took the test earned scores
that were less than or equal to your score.
Frequency Distribution
Table
Frequency distribution A
tabulation of the number
of individuals in each
category on the scale of
measurement.
Age of US presidents at their
respective inauguration
Presidential Ages at
Inauguration
1. Get the range of the ages of the presidents
42 to 69
2. Decide on what class size to use
Class width of 5 from 40-44, 45-49...
3. Construct your frequency distribution table
FDT: Ages of the presidents at inauguration
Class size frequency
Relative
frequency
Cumulative
frequency
Relative Cumulative
Frequency
40-44
2
2/43 = 4.7%
2
2/43 = 4.7%
45-49
6
6/43 = 14.0%
8
8/43 = 18.6%
50-54
13
13/43 = 30.2%
21
21/43 = 48.8%
55-59
12
12/43 = 27.9%
33
33/43 = 76.7%
60-64
7
7/43 = 16.3%
40
40/43 = 93.0%
65-69
3
3/43 = 7.0%
43
43/43 = 100%
Total
43
Constructing your OGIVE
Was Bill Clinton a
young president?
According to our ogive, it
shows that Clinton’s age
places him at the 10% RCF
mark. Therefore Clinton was
younger than about 90% of all
the US presidents based on his
inauguration age.
Let’s find the
distribution of the
height of all the
students in room
34 during this
period.
Your turn!
Height of 2011-2012 AP Statistics Students of BHS
Range:
Class width
and size:
73 - 59 = 14
Width: 3
Size: 58-60; 61-63; 64-66;
67-69; 70-72; 73-75
FDT: Height of 2011-2012 AP Statistics
Students of BHS
Class size frequency
Relative
frequency
Cumulative Relative Cumulative
Frequency
frequency
58-60
2
2/26 = 7.7%
2
2/26 = 7.7%
61-63
8
8/26 = 30.8%
10
10/26 = 38.5%
64-66
4
4/26 = 15.4%
14
14/26 = 53.8%
67-69
6
6/26 = 23.1%
20
20/26 = 76.9%
70-72
4
4/26 = 15.4%
24
24/26 = 92.3%
73-75
2
2/26 = 7.7%
26
26/26 = 100%
Total
26
Ogive: Height of 2011-2012 AP
Statistics Students of BHS
Vocabulary Summary
histogram
Individuals
outlier
Stemplots
variables
categorical
Dotplots
spread
quantitative
percentile
center
FDT
shape
ogive
Individuals
skewness
Statistical tools
Describing SOCS and skewness
Constructing dotplots and stemplots
Describing the SOCS of your distribution
Creating histogram
Generating histogram using graphing calculator
Organizing data by FDT
Constructing ogive and finding percentile using ogive.