Introduction to Affinity
Diagrams and Pareto Charts
1
80/20 Rule (Pareto’s Law) “Vital few and trivial many”
20% of effort is responsible for 80% of the results, which means that a
few (20%) efforts are vital and many are trivial
Focuses on what typically happens, not the multitude of exceptions
20% EFFORT
80%
RESULTS
Source: F. John Reh, “Pareto's Principle—The 80-20 Rule,” About.com,
http://management.about.com/cs/generalmanagement/a/Pareto081202.htm
(accessed December 12, 2012).
2
Examples of 80/20 Rule
20% of people owned 80% of the wealth (Pareto’s original observation)
20% of defects cause 80% of the problems (Juran’s observation)
20% of customers cause 80% of the complaints
20% of customers generate 80% of the revenue
20% of the product range generates 80% of the profit
20% of the sales force generates 80% of the sales
20% of the staff accounts for 80% of the lost work days (absences)
3
Pareto Chart (1 of 3)
Description
A bar graph in which:
The lengths of the bars represent frequency.
They are arranged with the longest bars on the left and the shortest to the
right.
300 100%
90%
250
244
80%
70%
200 187
60%
150 50%
40%
100 92
30%
45 20%
50
10%
7
0 0%
Blue Black Red Green Yellow
4
Pareto Chart (2 of 3)
The “Other” Bar
Represents a number of items with a small number of occurrences
aka “the trivial many”
300 100%
90%
250
244
80%
70%
200 187
60%
150 50%
40%
100 92
30%
45 20%
50 33
10%
7
0 0%
Blue Black Red Green Yellow Other
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Pareto Chart Example (Negative Attribute #1)
Customer Complaints 100%
250 90%
80%
200 70%
Cumulative Percent
60%
150
Number
50%
Vital few Trivial many
40%
100
30%
20%
50
10%
0 0%
Parking difficult Rude sales rep Poor lighting Confusing layout Limited sizes Clothing fadedClothing shrank
Count Cumulative Percent
Source: Based on “Pareto chart (Pareto distribution diagram),” WhatIs.com, http://
whatis.techtarget.com/definition/Pareto-chart-Pareto-distribution-diagram (accessed December 11, 2012).
6
Pareto Chart Example (Negative Attribute #2)
7
Pareto Chart Example (Positive Attribute)
Pareto Analysis - POSITIVE Comments (n=43) total: 43
30 100% Category Frequency/Quantity Cumulative %
Friendly Tech 27 62.79%
90% Explained Procedure 6 76.74%
25 One Stop Visit 4 86.05%
80% Walked to Lobby 2 90.70%
Courtesy Call 2 95.35%
70%
20 CD of Exam 1 97.67%
60% Tech Gender Preference 1 100.00%
15 50%
40%
10
30%
20%
5
10%
0 0%
Gender …
Exam
CD of
Courtesy
Friendly
Procedure
Walked to
One Stop
Explained
Tech
Tech
Lobby
Visit
Call
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Pareto Chart (3 of 3)
When to Use a Pareto Chart
When analyzing data about the frequency of problems or causes in a
process
When there are many problems or causes and you want to focus on the
most significant (80/20 rule)
When analyzing broad causes by looking at their specific components
When communicating with others about your data
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Affinity Mapping
Logical Grouping of Ideas
Helps to synthesize large amounts of data by finding relationships between ideas
More art than science
When to Use
Brainstorming causes or solutions
Analyzing qualitative “voice of the customer” feedback (survey/interview)
Fishbone diagrams
Random Ideas Affinity Diagram
Theme Theme Theme
1 2 3
Source: Based on “Affinity Diagrams: Organizing Ideas Into Common Themes,”
MindTools, http://www.mindtools.com/pages/article/ newTMC_86.htm
(accessed December 11, 2012).
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Affinity Mapping – Example
Cause Post-It Notes
Drop Down Coding Error Wrong option selected
(1) Wrong info Why was there
(2) Wrong people
(3) Wrong people info (not enough review)
an incorrect coding
Training Lack of knowledge (options available) of the engineering analysis?
(1) Not everyone is familiar with FFRP tool
(2) Not enough info about new tool development
Too Many People Entering Analysis Several groups entering data
Common Language (Terminology) Inconsistent definition of codes
Multiple people entering data, each with their own interpretation of the data they have been given
Different names for different components (MA's)
Similar choices for same failure mode
Material "root cause" may have different definitions from different sources (vendors / external or
internal groups)
Incorrect info from engineer
Root cause not clear
Process Not Clear Process not widely communicated & understood
Choppy work flow
No one method of communication
Hardware should follow system assignment flow
Drop Downs Too Complex Too many ways to log the same thing
Items in drop downs do not make sense
Too much detail required
Too many choices per field
Too many fields to fill out
UI Not Intuitive User Interface not intuitive
Hard to understand -- no easy flow of entering failed parts / root cause
Outdated Drop Downs (Maintenance) Lack of appropriate drop down selections to identify the issue
Drop down not maintained - (a) very little SW categories & (b) some do not make sense
Outdated drop downs
Incorrect drop down menus available
Option for root cause not available
Only shows what is currently available -- people use "best fit" 11
Affinity Mapping – Example (cont’d)
Group Cause Post-It Notes
People Drop Down Coding Error Wrong option selected
(1) Wrong info
(2) Wrong people
Why was there
(3) Wrong people info (not enough review) an incorrect coding
People Training Lack of knowledge (options available) of the engineering analysis?
(1) Not everyone is familiar with FFRP tool
(2) Not enough info about new tool development
People Too Many People Entering Analysis Several groups entering data
People Common Language (Terminology) Inconsistent definition of codes
Multiple people entering data, each with their own interpretation of the data they have been given
Different names for different components (MA's)
Similar choices for same failure mode
Material "root cause" may have different definitions from different sources (vendors / external or
internal groups)
Incorrect info from engineer
Root cause not clear
FFRP Process Process Not Clear Process not widely communicated & understood
Choppy work flow
No one method of communication
Hardware should follow system assignment flow
FFRP SW Tool Drop Downs Too Complex Too many ways to log the same thing
Items in drop downs do not make sense
Too much detail required
Too many choices per field
Too many fields to fill out
FFRP SW Tool UI Not Intuitive User Interface not intuitive
Hard to understand -- no easy flow of entering failed parts / root cause
FFRP SW Tool Outdated Drop Downs (Maintenance) Lack of appropriate drop down selections to identify the issue
Drop down not maintained - (a) very little SW categories & (b) some do not make sense
Outdated drop downs
Incorrect drop down menus available
Option for root cause not available
Only shows what is currently available -- people use "best fit"
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Affinity Mapping – Manager’s Meeting Example
Expectations of Manager's Meeting total: 80
25 100% Category # Cum %
Informational 22 27.5%
90% Priorities 14 45.0%
Financial Health 10 57.5%
20 80% Informational - System 6 65.0%
Share Best Practices 6 72.5%
70%
Networking 6 80.0%
15 60% Safety 5 86.3%
Motivational 4 91.3%
50% Q&A 4 96.3%
Interactive Feedback 3 100.0%
10 40%
30%
5 20%
10%
0 0%
Share Best …
Informatio…
Informatio…
Financial…
Interactive…
Safety
Priorities
Q&A
Motivational
Networking
Blue – Top 3 Green – 80 / 20 Rule
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