RE: Red Bead "simulator"

["Prevette, Steven S" <Steven_S_Prevette@rl.gov>]

 Isn't the fact that this is a mechanical sampling process and takes
into account variations in paddle hole size, bead size and weight etc.
an important contributor of the results?

Dr. Deming would usually follow up the Red Beads with a discussion of
mechanical sampling.  He would tell folks the counts of beads in the
supply (800 red and 3200 white) and ask the audience what the expected
number of red beads were per paddle pull, and someone will always say
"20%"  to which he would then answer "Wrong".  I believe he used a story
of sampling ore from a trans-Pacific shipment to Japan as an example of
the dangers of random sampling.  Also, there are charts to show that the
various combinations of paddles and beads that Dr. Deming used led to
statistically significant different results from combination to
combination, and were all different than 10.


Steve Prevette
Occupational Safety and Health
Fluor Hanford, A Fluor Government Group Project
ASQ Certified Quality Engineer
steven_s_prevette@rl.gov
509-373-9371