Spider Charts:
A Training Course
Spider Charts Training Agenda
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What Are Spider Charts?
How Can Your Organization Use Them?
Developing Spider Charts
Spider Charting Exercise
Summary
References
What Are Spider Charts?
• A graphical way to compare data
• Displayed in a “web-like” form
• Used to evaluate multiple alternatives
based on multiple criteria
How Can Your Organization Use Spider Charts?
• Do you want to graphically compare multiple
potential projects?
• Do you need to analyze the strengths and
weaknesses of different supply chain strategies?
• Are you finding it difficult to make logical
comparisons between business opportunities?
If your answer is yes, then Spider Charts may be your solution!
Developing Spider Charts (Six Easy Steps)
1.
2.
3.
4.
Identify the alternatives to be compared
Generate criteria to rate each alternative
Rate each alternative based on criteria
Draw and label the axis arms of the chart (one
arm for each criterion)
5. Draw and label each alternative’s ratings on the
chart, connecting between arms
6. Analyze the chart
Developing Spider Charts
What a Finished Spider Chart Might Look Like:
Developing Spider Charts
Step 1 – Identify the alternatives to be compared
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Spider Charts could be used to compare:
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Potential Projects
Performance of Vendors
Employee Performance
No more than 5 (five) alternatives should be
compared using Spider Charts
Developing Spider Charts
Step 2 – Generate criteria to rate each alternative
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Projects can be rated based on risk, return, initial
cost, or any other criteria
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At least three criteria must be used, more may be
helpful, but more than seven may be too complex
Developing Spider Charts
Step 3 – Rate each alternative based on criteria
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It is helpful to standardize ratings to some uniform
scale (for example 0-10, or 0-100%)
Developing Spider Charts
Step 4 – Draw and label the axis arms of the chart
(one arm for each criterion)
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If there are five criteria (C) on a scale of 0-10:
C-1
10
C-2
5
C-5
0
C-4
C-3
Developing Spider Charts
Step 5 – Draw and label each alternative’s ratings
on the chart, connecting between arms
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Using different colors for each alternative is best
C-1
10
C-2
5
C-5
Alternative 1
0
Alternative 2
C-4
C-3
Developing Spider Charts
Step 6 – Analyze the chart
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For this example, possible analyses might include:
Alternative 1 is better in
criterion 1, 2 and 5
C-1
10
C-2
5
C-5
Alternative 2 is better in
criterion 3 and 4
0
Alternative 1
Alternative 2
The largest difference is
found in criterion 4
C-4
C-3
Spider Charting Exercise
• Now, let’s go through an exercise to create a
Spider Chart
• Suppose you want to compare how well three
different vendors have delivered goods on time
over the past five years.
• You have the following data:
Spider Charting Exercise (continued)
Data
On-time Delivery Percentages
Vendors:
Year:
AppleGate
Patriot, Inc.
Franklin
1
45%
67%
83%
2
57
64
65
3
68
70
77
4
63
66
91
5
75
71
55
Spider Charting Exercise (continued)
• Refer to the data on the previous slide and use
the Six Steps to create a Spider Chart comparing
the three vendors
• Hint: The “criteria” used in this example are
actually the five years
Spider Charting Exercise (continued)
As a reminder, here are the Six Steps:
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Identify the alternatives to be compared
Generate criteria to rate each alternative
Rate each alternative based on criteria
Draw and label the axis arms of the chart (one arm for
each criterion)
Draw and label each alternative’s ratings on the chart,
connecting between arms
Analyze the chart
Spider Charting Exercise (continued)
More hints for the example problem:
1. The alternatives are the three vendors
2. The criteria are the five years
3. The ratings are given as the percentages
4. Your chart should have five arms (for the five
years)
5. You should have drawn three “webs”, one for
each vendor
6. What does the chart tell you about the vendors?
Spider Charting Exercise Solution
Here is what your Spider Chart should look like:
1
100%
50%
AppleGate
5
2
Patriot, Inc.
0%
Franklin
4
3
Spider Charting Exercise Solution
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This Spider Chart was developed using
Microsoft Excel, which is a quick and flexible
way to make the chart
To make it in MS Excel, input the data in the
cells, then “Insert” a “Chart” and select “Radar”
as the Chart Type
1
100%
50%
AppleGate
5
2
Patriot, Inc.
0%
Franklin
4
3
Summary
• Spider Charts are very useful for visually
comparing a few alternatives
• Just follow the Six Easy Steps to create your
own Spider Chart
• Microsoft Excel provides a quick and easy way
to create a Spider Chart
References (Where to Find More Information)
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http://www.internet4classrooms.com/excel_radar.htm
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The Spider Chart: A Unique Tool for Performance Appraisal, 1995, ASQC,
Rogers, Cephas B.
– Go to www.asq.org (the American Society for Quality website) and
search for “spider chart”
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http://www.asq.org/education/docs/radarchart.pdf
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Beyond Strategic Vision: Effective Corporate Action with Hoshin Planning,
Michael Cowley, 199, page 76.
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The Ultimate Six Sigma: Beyond Quality Excellence, Keki R Bhote, 2001,
page 180.