.: The Red
Bead Experiment :.
Introduction
This experiment can be conducted with a
Lightning Calculator Sampling Bowl or Sampling Box. While Dr.
Deming used 80% white beads and 20% red, you will find this
experiment done with 80% white and 20% colored. The colored
beads add another dimension to the demonstration. This will be
become self evident as the script is read.
This is a clever demonstration of the futility
of most management systems for improving quality. Dr. Deming
often refers to it as a stupid experiment that you'll never
forget. The experiment is described in a form similar to Dr.
Deming's presentation in his seminars. As will be described at
the end, it can also be adopted for very small groups and even a
one on one presentation.
The experiment starts with a sampling device
that has 80% white and 20% colored beads, normally red beads,
hence the name "red bead experiment". The fact that
the some sampling devices have various colored beads instead of
all red is of no consequence, the experiment works just as well.
It is necessary however to have 20% colored beads to go along
with the text of this demonstration. If different colored beads
are used instead of all red, then the colors can represent
different kinds of defects. (This will become clearer as the
demonstration is described.)
The objective of the bead factory in the
demonstration is to make white beads. The customer will not
accept anything but white beads, all colored beads are
defective. The colored beads themselves represent defects in an
organization's business processes. They represent a faulty
machine or tool, a bad engineering design, a defective part, a
procedural flaw, an unreasonable change request, ... all the
things that can and do go wrong with a process. Supervisors and
management control the number of red bead in the processes that
are given to the workers. Now. let's proceed assuming that
management has developed and purchased the white bead process
for the workers of this experiment.
The Experiment
The instructor should take on the role of the
department foreman or department supervisor and first of all
selects his work team. Realizing that one of the objectives of
this demonstration is to point out management prejudices, the
instructor can use whatever slogans or phrases he believes fit
his particular audience. It many start like the following.
Foreman: Okay I need eight bodies.
(Pointing to people he wants to select) Can you count? Okay
you're hired . Can you push buttons? Okay you're hired. You
don't have to think, you just have to do what I tell you. You'll
be on an apprenticeship for a while and if you work out we'll
hire you. We believe in high quality. We need good people.
So the process goes until all nine people are
selected. The roles they will perform are as follows:
Foreman (the instructor)
Worker 1 - Bob (assuming fictitious names for
this description)
Worker 2 - Dorothy
Worker 3 - Henry
Worker 4 - Calvin
Worker 5 - Carol
Worker 6 - Judy
Inspector 1 - Ron
Inspector 2 - Marty
Chief Inspector - Darwin
What will happen is that each worker will take
turns drawing a sample of 50 from the sampling device. If you
are using a sampling bowl then use the 50 hole paddle. If you
are using a sampling box then designate the 50 hole pattern that
you will use. This can be done verbally, mark on the face of the
box with a water based transparency marker, or mask off the
excess holes with masking tape, etc. Once a sample is drawn,
then it will be checked by both inspectors (this high quality
company has 200% inspection) who will independently write down
the number of colored beads they count and show it to the chief
inspector. The chief inspector will compare the counts, record
the information on a data sheet and a graph, and then announce
the number of colored beads drawn in the sample. The data sheet
will show the names of the six workers and how many colored
beads they each draw for the four days of the experiment. The
data sheet will look like the sample data shown in figure 1. The
graph will have six plot points for each day for four days and
look like the graph in figure 2. These graphs can be set up on
chart pads or overhead transparencies.

After the samples are counted, the beads are
returned to the sampling device and another sample is drawn
(shaking the box or mixing the bowl adds to the demonstration).
Obviously the percent defective is a constant 20% but the actual
percentage will vary with each sample due to sampling error and
this is where the spoof begins. While there are some lessons in
statistics than can be taught from this experiment, the real
punch line is in the way the instructor conducts the
demonstration and allows people to see themselves and the
futility of management practices for improving quality. Each
instructor has to know is audience and how far he can push his
points without turning them off.
As the experiment is carried out over the four
days the instructor uses the results of the samples to make his
points. Realizing that the data will most likely vary between 1
and 19 (determined from the control chart calculations for UCL
and LCL for a process that is 20% defective and sample sizes of
50). There are a variety of points that can be made. The exact
order that the instructor will make the points will be dependent
on the actual data developed in the experiment. However, after
24 samples you will have enough high and low readings along with
increasing and decreasing trends to make all the points.
Clear Instructions
The first point of the demonstration has to do
with giving clear instructions. Management often believes that
if they make the objectives clear then the problems will go
away. It could go something like the following:
Foreman: Bob you know that our job is
to make white beads, the customer will not accept colored beads.
You make white beads by first of making sure that the material
is well mixed. If it is not mixed well you will have trouble
making white beads. (Demonstrate how you want the box shaked or
the beads mixed in the bowl) You then turn the box over and hold
it completely flat while you push this button on the end and
white beads will fall into the holes. (If you are using a
sampling bowl then the describe how the paddle is to be used to
draw a sample.) Place the paddle into the bowl at the end, scoop
deep into the beads and raise the paddle slowly at an angle of
precisely 30 degrees and let the extra beads roll off the
paddle. Now I've described the job for all you very clearly. I'm
sure that all of you can now make white beads. Bob, would you
please make our first batch of white beads.
Bob draws the first sample and shows it to the
inspectors who record the count and they show it to the chief
inspector. He then announces that we have 14 red beads. If
colored beads are used then let red beads be red defects, green
be green defects, yellow be yellow defects, etc. Still have the
chief inspector count and record the total number of colored
beads, but have him also report the different number for each
color. The instructor can then use this to attach more blame to
the worker, i.e. "Yellow defects, you know they are the
worst kind and most costly to repair," and so on.
Foreman: Bob I've told you that the
customer will only accept white beads, colored beads are not
acceptable. Did you mix the material and hold the box completely
flat like I told you? (Did you hold the sampling paddle at
precisely 30 degrees?)
Bob: Yes I did
Foreman: Well you must not have been
paying attention. Dorothy can you please make us a batch of
white beads? Remember all that I've told you. (repeat the
appropriate instructions again).
Dorothy draws a sample and it comes out to be
12 colored beads.
Foreman: Well Dorothy that is better
than Bob, but you must not have been paying attention either.
Let me repeat the instructions once again. (repeat the
appropriate instructions) Henry will you please run this
process. Remember that the customer will only accept white
beads.
Intimidation
Henry then draws a sample and it comes out to
be 15.
Foreman: Henry I need to talk to you.
Didn't you hear me when I gave all these people instructions on
how to make white beads? What were you doing at the time,
dreaming of some date you were going to have with Judy? I
thought you said you wanted a job. We bring you here, give you
clear instructions, show you how to make white beads and you
still don't do it. What's the matter with you? Now I'm telling
you people, you all better start paying attention or I'll have
to fire all of you. Calvin it's your turn.
Praise and Comparison
Calvin draws a sample and it comes out at 8
colored beads.
Foreman: Now that's much better. Calvin
you are catching on. Calvin got the same instructions as the
rest of you and he is now beginning to master the process. He
was almost twice as good as Henry. We are going in the right
direction now. Henry, you especially need to watch Calvin and
see how he did it. In fact, the rest of you should all watch
Calvin and see how he does it. Carol, it is your turn.
Banners and Slogans
Carol draws a sample and it turns out to be
10.
Foreman: Carol, I told you to watch
Calvin. He knows how to do it. Now all of you listen up. We have
firm quality standards at this factory. Didn't you read the
quality first banner over the door of the factory? See that
poster on the wall over there, it says "Satisfied customers
are happy customers and that means they will buy more."
Quality is critical to our survival as a company and you know
what that means for all our jobs. This company has to get the
silver star quality award. It is crucial to our success in the
market place. Judy please show us how it's done.
Judy draws and sample and it come out to be 6.
The foreman then walks over and talks to the chief inspector.
Foreman: Darwin, here is a prime
example of quality improvement. You see once I pointed out to
everyone that we are really serious about quality at this
factory, people started to improve. Judy ran the best batch of
white beads that we've seen so far. I think that we need to put
a poster by everyone's machine instead of just a few on the wall
that we have. You know if we buy some of those quality first
buttons we all could wear one and give one to every employee
that improves. I'm sure that we can drive the point home more
about quality. While today wasn't the best I'm sure we'll do
better tomorrow. (while walking over to Judy) Judy, excellent
job. Keep up the good work.
Incentives
Tomorrow comes and the foreman asks Bob to run
his batch of white beads. Bob runs his sample and it comes out
at 10.
Foreman: Bob you've done better than
you did yesterday but we are still going in the wrong direction.
I've talked this matter over with our management and we are
going to institute a quality bonus for everyone who runs good
parts. If you guys and gals will all do better we will have a
big pizza party and bonus for everyone.
After the bonus scheme is in place Dorothy
draws 5, Henry draws 6, and Calvin draws 8 colored beads. The
foreman then talks to the audience as if they were the
management. He is explaining the value of the bonus scheme.
Foreman: Well after we instituted the
bonus scheme that I recommended things got better immediately.
While things have been going up and down we are still much
better than we were yesterday. I think that our people are
finally getting the message and all our efforts with the new
quality banners and quality first buttons are paying off. We are
definitely on the road to zero defects. I think that we should
design another button with a big zero in the middle that is
surrounded by gold stars that we can present to our best
employees. In fact I would like for one of you to speak at our
employee meeting and tell them about this exciting new zero
defects button program.
Blame
Carol and Judy then each draw 11 colored
beads. The foreman is very upset that things are going bad after
he has told management that things were improving. He then goes
over to the chief inspector and discusses the problem with him.
Foreman: Darwin, I'm really upset.
These people don't care. Here you give them a good job and show
that it is possible to improve and what do they do, ignore you
and make life easy for themselves. I know that our incentive
scheme was working, look at the results. I think Carol and Judy
are spending too much time talking to one another and not paying
attention to their job. I think that I'll warn both of them
about their performance and tell them if I catch them talking
again that I'll have to discipline them.
Performance Appraisals
This process continues again and again until
all 24 samples have been taken. The data is then summarized for
display and the supervisor then rates everyone's performance.
The data is then placed on an overhead projector or summarized
on a chart pad.
Foreman: Bob, you started off bad and
then improved slightly. You have got to do better. Dorothy, you
started off bad, then you improved, then you fell off the wagon
again, and then improved again. You need to pay closer attention
to your work and gain more consistency. Henry, you started off
terrible and then you finally caught on. You have the same
problem as Dorothy, you need more consistency. Calvin, your the
best employee in the department, but you still have room for
improvement. You could be the first employee to earn the zero
defects button that the manager talked about at the employee
meeting. Carol, your performance needs to improve. Your overall
rating was good. You can do better if you stop all that talking
with Judy I warned you about. Judy, you need to pay attention to
your work. You started off good and something must have
distracted you. I think it was all the talking with Carol.
The foreman should now take on the role of
explaining the results to management as he turns to the
audience. The focus can now be on the graph and the noting of
the various trends. The same praise and blame is offered for the
trends. An evaluation of the trends for each day and an overall
comparison of each of the workers may be appropriate at this
point, as you try to present the results with the best possible
explanation. The supervisor would then promise that they can do
better and explain all the new quality programs that are in
place to address the problems, i.e. posters, etc. He would make
special note that he had warned the Judy and Carol and gave them
unfavorable performance evaluations.
Discussion of the Experiment
The instructor then steps out of his foreman
role and now asks questions as an instructor in order to get the
class to evaluate what has happened.
What was the average of number of defects for
the experiment (X-Bar)? Take the total number of colored
beads(220) and divide by 24. (X-Bar=220/24=9.2 for this
experiment) Ask them what they expected the average to be and
why. Facilitate a discussion that gets them to see that the
average has got to be 20% defective since we know that there was
a fixed 20% defective all the time in the sampling device.
Explain that "p bar" is merely the average percent
defective for a given sample size. Given that we had 20%
defective, and samples of 50, 20% of 50 is 10. In our example
the actual average was 9.2. This will vary slightly with each
demonstration.
Next show that a simple p-Chart would have
control limits of 1 and 17. This is determined by using the
following formulas:
P Bar = 220 / 6 * 4 * 50 = .18
UCL or LCL = X Bar ± 3 Sq
Root [(X-Bar)(1-P Bar) ]
9.2 ± 3 Sq Root
[(9.2)(.82) ] =
or
9.2 ± 8.24 = .96 to 17.44

What this means is that given a 20% defective
process, and with sample sizes of 50, that the number of colored
beads will vary over 99% of the time between 1 and 17 just due
to random chance. In the demonstration we knew that it was
random chance because we controlled the experiment by virtue of
a constant number of beads. In actuality, we have what Dr.
Deming calls a "stable process," or a system that is
varying only because of random chance. This random chance is
also referred to as only being affected by "chance or
common causes." Note that a stable process may still turn
out faulty items.
While there are a number of options for
discussing the results of the experiment, the instructor can
discuss the following points independently or use the Deming's
14 points slide in the appendix as a guideline.
Using the 14 point slide as a reference, add
the following comments for each respective point:
Dr. Deming's Fourteen Points
1. Create constancy of purpose for
improvement of product and service. The red bead experiment
is a process. The only way to actually improve the process was
to change the number of red, or colored beads, in the container.
While the process the data varied showing good and bad trends,
the foreman was deceived into thinking his actions were
impacting the process when in fact only random variation was
taking place. The focus of improvement has to be on changing
business processes, not blaming people.
2. Adopt the new philosophy. Management
controls the number of red beads in a process initially since
they design the products, purchase the machines or facilities,
and establish the operating procedures. Once a system is in
installed, management has to find a way to reduce the number of
red beads if they want to improve the process. The problem is,
that in most cases management does not know where the red beads
are, but the workers do. It is only through a joint effort
between management and workers that processes can be improved.
3. Cease dependence on inspection to
achieve quality. While two inspectors counted the number of
red beads, you can note how often the count may have differed.
Point out the non-value added role of the inspectors in actually
changing the process.
5. Improve constantly and forever every
process for planning, production, and service. The number of
red beads in this experiment causing the level of variation was
totally controlled by management. The workers were totally
helpless in affecting the number of red beads that were drawn.
In real life however there usually are some things that the
workers can do to create improvement. But according to Dr.
Deming common or chance causes are controlled my management
(usually 85% of the problem), and local faults or special causes
(15%) are controlled by workers. Hence the major responsibility
for process improvement (85%) lies with management changing the
systems.
6. Institute training on the job. Point
out how a simple understanding of p-chart statistics would have
helped the foreman recognize that the process was really a
stable process and that the variation he was experiencing was
really normal and expected. While the foreman gave clear
instructions of what was expected to the workers on the first
day, this alone did not create quality. Management clearly
telling workers what they want does not mean that workers can
achieve it.
8. Drive out fear. If management really
wants to learn where the red beads are in a process so they can
remove them, they must be willing to listen and stop blaming
workers for poor results. Did the intimidation or comparisons of
the workers have any real affect on the outcome of the red bead
experiment? Management thought so at the time, but in reality
the results were still caused by random variation.
10. Eliminate slogan, exhortations, and
targets for the workforce. In the same way that intimidation
and comparisons between workers did not impact the outcome of
the red bead experiment, neither did the slogans, buttons, or
incentive schemes. The understanding and focus has to be on the
process and it's capabilities.
12. Remove barriers that rob people of
pride of workmanship. Eliminate the annual rating or merit
system. How do you think the workers felt about their
performance appraisals? Do you think that it motivated them to
do better? Has anyone ever had a performance appraisal where the
comments were similar to same mumbo jumbo and cliches that were
fed to the workers in this experiment?
14. Put everyone in the company to work to
accomplish the transformation. If management does not
actually solicit employee input on solving business processes
they are passing up a golden opportunity for improvement.
Everyone at all levels of the organization has to be focused on
quality improvement.
In summary, this demonstration can be a lot of
fun while still making a number of dramatic points. The use of
participants keeps people involved and active. If you get
involved and act out the roles, the class will do likewise. The
more the instructor customizes the experiment to the class the
better it will be received. Use phrases that are common to the
work place. Finally, the power of the experiment is only limited
to the creativity of the instructor.
Adaptations of the Experiment
Small Audiences - The previous
description was designed for classroom use. There may be
situations were it would be advantageous to perform the
experiment on a smaller scale and more quickly. To abbreviate
the experiment assume that the conversations take place between
the foreman and one employee. Explain the requirements and then
let the employee begin sampling. As data will of course
immediately show red beads, the various management solutions can
be stated to the employee. Cover the following issues between
each sample like intimidation, unfair comparisons, praise,
banners and slogans, providing incentives, and blame. Record the
results of each sample and then give the person a performance
appraisal at the end. Discuss how the employee felt as you were
explaining to him all the management solutions for improvement.
Use of a Customer - Instead of having
two inspectors and a chief inspector let one person review the
bead sample who will be the customer. Pre-arrange with the
customer to act like an irate customer when he gets different
colored beads, etc.
Rework Department - If you are using a
sampling bowl and would like to make a point about the cost and
inconvenience of rework pick another worker to be a rework
operator. Give them a bottle of white out correction fluid and
tell them to paint some of the red beads white. Note that this
can be messy and you need to also have a bottle of correction
fluid solvent and a rag available for clean up of the operator
and the beads when you are finished. Letting them work on three
to four beads will be sufficient. Make the point about how poor
a job they have done in rework. Show the production workers all
the problems they have caused. Let the inspectors or customer
comment on the quality of the rework job.
Bead Box versus Sampling Bowl - While
both devices can be used for demonstration purposes each has its
own advantages. The bead box is of course totally self contained
and is easily transported. Students can handle and play with the
box as it is passed around. The Sampling Bowl on the other hand
is very visual and works well with large audiences. It provides
flexibility in determining the colors and percentages as well as
sample sizes, etc. As previously mentioned, different colored
beads can be used to represent different types of defects and
problems
The Fourteen Obligations
of Top Management
-
Create constancy of purpose for improvement
of product and services.
-
Adopt the new philosophy.
-
Cease dependence on inspection to achieve
quality.
-
End the practice of awarding business on
the basis of price tag alone. Instead, minimize total cost by
working with a single supplier.
-
Improve constantly and forever every
process for planning, production, and service.
-
Institute training on the job.
-
Adopt and institute leadership.
-
Drive out fear.
-
Breakdown barriers between staff areas.
-
Eliminate slogans, exhortations, and
targets for the work force.
-
Eliminate numerical quotas for the work
force and numerical goals for management.
-
Remove barriers that rob people of pride
of workmanship. Eliminate the annual rating or merit system.
-
Institute a vigorous program of education
and self improvement for everyone.
-
Put everybody in the company to work to
accomplish the transformation.
Dr. W. Edwards Deming
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