This document provides instructions and examples for creating different types of data displays, including stem-and-leaf plots, histograms, back-to-back stem-and-leaf plots, and box-and-whisker plots. It includes examples using temperature data and adoption prices for dogs. Key terms and how to interpret the visuals are explained through mini lessons within the document.
2.
Slide 3: Stem-and-Leaf Plots
Slide 6: Mini Lesson: What If
Slide 8: Mini Lesson Key 1
Slide 9: Mini Lesson: Key 2
Slide 10: Histogram
Slide 12: Mini Lesson: The Difference Between Bar
Graphs and Histograms
Slide 13: Back to Back Stem-and-Leaf Plot
Slide 17: Box-and-Whisker Plot
Slide 20: Mini Lesson: Box Position
Table of Contents
3.
Example Problem:
In the town of Sugar Pine, the next high
temperatures for the next ten days are below.
63 F°, 63 F°, 65 F°, 66 F°, 73 F°, 75 F°, 78 F°, 81 F°,
81 F°, 82 F°
Now we need to look at all the different
numbers in the tenth place on the next slide.
Stem-and-Leaf Plots
4.
63, 63, 65, 66, 73, 75, 78, 81, 81, 82
Now we need to look at all the different
numbers that aren’t in the one’s place, there is
6, 7 & 8. We will place these on one side of the
line and place the numbers that were tied to
those numbers on the other side of the line on
the next slide.
Stem-and-Leaf Plots
5.
6 3 3 5 6
7 3 5 8
8 112
Stem-and-Leaf Plots
Now that that is done, we need to give it the
right format with a title, units and key. This will be
on slide 7.
Note: There are not any spaces between the numbers.
6.
If one of the temperatures had been 9 F° and if
one had been 134 F° and if one had been
3445 F°, it would have been looking like the
below.
Mini Lesson: What If
0 9
1 34
3 445
7.
6 3 3 5 6
7 3 5 8
8 112
High Temperatures For the Next Ten Days
(Degrees Fahrenheit)
Key: 6 I 3 = 63
8.
A key can be ANY number in the problem.
Mini Lesson Key 1
9.
A key tells you what is between the lines, an
example could be if you were working with
decimals and you had the whole number on the
left side and the other number on the other side.
If your key number was 1.9 then the key would
look like
1 I 9 = 1.9
Mini Lesson: Key 2
10.
We will use the same set of numbers
63 F°, 63 F°, 65 F°, 66 F°, 73 F°, 75 F°, 78 F°, 81 F°,
81 F°, 82 F°
We will arrange these on a graph, instead of
categories we will have number ranges, for this
one I will use a number range of 10, the amount
of numbers that fit into that range will add up on
the bar.
Histogram
11.
High Temperatures For
the Next Ten Days
60 - 69 70 - 79 80 - 89
1
2
3
4
5
6
7
Frequency
(Degrees Fahrenheit)
12.
Mini Lesson: The Difference Between
Bar Graphs and Histograms
The key differences are that the bars touch in a
histogram and they don’t in a bar graph.
Another example is that the categories on a bar
graph are words and on a Histogram they are
numbers.
13.
The back to back stem-and-leaf plot shows the
prices (in dollars) of Poodles and Chihuahuas at
a breeder. Compare the prices of adoption for
the two dogs.
This plot is on the next page.
Back to Back Stem &
Leaf Plot
15.
Poodle
3 1 0
7 5 5
8 7 6 5 4
8 8 5 5
Back to Back Stem &
Leaf Plot
4
5
6
7
Chihuahua
0 0 2 3 3
1 1 2 3 5 5
0 2 2
2
Key: 4 I 6 I 0 = $64, $60
So this is how it works, cover up the Poodle side with your hand. Look at the other stem-
and-leaf plot on slide 5, don’t they look similar? You read the Chihuahua side like the other
plot was read. To read the Poodle plot, cover up the Chihuahua side and imagine the
“middle column” on the left side.
The key is read much the same way, when you cover up the 4 and look on the other side
of the equal, you see $60. When you cover up the 0 and switch the 4 and 6 with your eyes,
you see 64 or $64.
16.
Poodle
3 1 0
7 5 5
8 7 6 5 4
8 8 5 5
Back to Back Stem &
Leaf Plot
4
5
6
7
Chihuahua
0 0 2 3 3
1 1 2 3 5 5
0 2 2
2
Key: 4 I 6 I 0 = $64, $60
Now we need to find the median of the prices of Poodles and the median of prices for
Chihuahuas. To do this we will cross out the right and left sides of each one separately to
find the middle or median.
Poodle Median: 67
Chihuahua Median: 53
Conclusion: In general, Poodles cost more than Chihuahuas from breeders.
17.
Find the median, lower quartile and higher
quartile. Also find the maximum and minimum.
Box-and-Whisker Plot
18.
20 22 27 31 46 47 54
Median: 31, the number that splits it in half.
Lower Quartile: 22, the half of the smaller numbers
Higher Quartile: 47, the half of the larger numbers
Minimum: 20, smallest number.
Maximum: 54, biggest number.
Now you need to place these things on a
numbered line (next slide).
Box-and-Whisker Plot
19.
10 20 30 40 50 60 70 80 90
Box-and-Whisker Plot
minimum
maximum
median
Higher Quartile
Lower Quartile
20.
It doesn’t matter that the box was floating since
there is no scale, but if there was a scale, the
box would be would be flat on the line.
Mini Lesson: Box
Position
