stem and leaf plot
TRANSCRIPT
Stem and Leaf PlotA WAY TO ORGANIZE DATA
PREPARED BY SUSA N VO
Advantages
• Sorts data quickly
• Gives an overview of the spread of the data
• Able to tell min value, max value and range in a glance.
A Stem and Leaf Plot is a special table where each data value is split into a "stem" (the first digit or digits) and a "leaf" (usually the last digit).
Example 1
The test scores of a class of 30 students are as follows:
83, 65, 65, 95, 70, 50, 73, 75, 98, 40, 75, 73, 95, 88, 88
35, 45, 47, 45, 78, 13, 100, 92, 84, 35, 68, 100, 97, 56, 8
The leaf will be the rightmost digit of each score;
the stem will be the other digits listed in ascending order.
Stem Leaf0 81 323 5 54 0 5 7 55 0 66 5 5 87 0 3 5 5 3 88 3 8 8 49 5 8 5 2 7
10 0 0
Scores spread at one glance
Highest Score: 100 (2 students) Lowest Score: 8
Example 2
The long jump distances (measured in meters) in a P.E. class of 30 students are as follows:
2.3, 2.5, 3.5, 6.5, 2.0, 2.3, 3.7, 4.5, 3.8, 4.0, 3.5, 6.1, 4.3, 3.8, 5.0
3.5, 4.5, 4.7, 4.5, 2.8, 6.3, 2.2, 3.2, 3.4, 4.5, 3.8, 5.0, 4.7, 3.6, 2.7
The leaf will be the tenth digit of each reading;
the stem will be the ones digits listed in ascending order.
Stem Leaf
2 3 5 0 3 8 2 7
3 5 7 8 5 8 5 2 4 8 6
4 5 0 3 5 7 5 5 7
5 0 0
6 5 1 3
Scores spread at one glance
Furthest distance: 6.5 m Shortest distance: 2.0 m
A Stem and Leaf Plot can also be used to make a comparison between two classes of scores.
We can draw them back to back as illustrated in the next example..
Example 3
Class A scores are: 76, 45, 58, 79, 82, 63, 76, 72, 58, 13, 45, 90, 72, 65
Class B scores are: 56, 34, 72, 89, 15, 97, 45, 34, 72, 65, 98, 12, 26, 64
The leaf will be the ones digit of each score;
the stem will be the tens digits listed in ascending order.
Class A Class B
3 1 5 2
2 6
3 4 4
5 5 4 5
8 8 5 6
5 3 6 5 4
2 2 6 9 6 7 2 2
2 8 9
0 9 7 8