Question of the Week:
What is the "Red Bead Experiment," and where can I learn more about it?
The Red Bead Experiment was developed by W. Edwards Deming, one of the foremost pioneers of quality. The experiment illustrates that it’s impossible to determine employees’ performance for the coming year based on their performance during the past year, because performance differences must be attributed to the system, not to employees.
To reproduce the experiment you need:
- Six people ("employees")
- 800 red beads
- 3,200 white beads
- A container large enough to hold all the beads
For the experiment, assume that the goal is for employees to produce white beads, because the customer will not accept red beads.
- The beads are placed in the container, and stirred or mixed until they’re randomized.
- The first of the six employees, blindfolded, selects 50 beads. The next employee repeats the blind selection process, and so on, until all six employees have chosen beads.
- Each employee counts his or her red beads.
The number of red beads gathered by each employee will vary. Because the selection of beads was a random process, the differences will fall within the limits of variation that could arise from the system.
The experiment shows that it would be a waste of management’s time to try to find out why, say, John "produced" four red beads and Valerie "produced" 15. Instead, Deming argued, management should improve the system, making it possible for everyone to produce more white beads.
Deming explains his Red Bead experiment in depth in the book in Out of the Crisis (MIT Press, 1986).
Additional reference material on the experiment:
Using Corrective Action to Make Matters Worse (By Not Considering Variation)
by Wallace Davis III
Quality Progress, Vol. 33, No. 10, October 2000
Logged-in Members/Subscribers: Instant Access. Or you can buy a PDF.
The Red Bead Experiment for Educators
by Ron Turner
Quality Progress, Vol. 31, No. 6, June 1998
Logged-in Members/Subscribers: Instant Access. Or you can buy a PDF.
Read more about Deming from ASQ's collection of "Honorary Member" biographies.
Visit the W. Edwards Deming Institute Web site.
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