Training%20technologists%20in%20experimental%20design

1
Training technologists in experimental design

• ??James M Cupello
• ??1999
• ??
• Research Technology Management.
•  Washington  ?? 42, Iss. 5  pg. 47

??????
2
Outliner Introduction

• Curriculum Content
• Teaching Skill
• Course Materials
• In-Class Experiments
• DOE Software
• Integration with Other TQM Tools
• Select Taguchi Methods
• In Conclusion

3
Introduction

• Statistically designed experiments have proven to
  be
• one of the few reliable weapons in the 20th
  century arsenal of globally competitive firms.
• RD managers would benefit greatly if they could
  identify the vital few outstanding courses from
  among the hundreds of academic and commercial
  ones available on this topic.
• Consequently, 7 best practices associated with
  such a world-class course are postulated.

4

• Curriculum Content
• "Curriculum content" and "teaching skill" are
  truly first among equals when looking at all
  seven best practices.
• (1) Calculating factor effects for simple
  two-level designs, preferably via a student
  exercise.
• (2) Inclusion of a thorough explanation of
  interaction effects, their importance and how
  they are calculated.
• (3) Introducing the concept of orthogonal arrays
  and how they are constructed for two-level
  designs.
• (4) A thorough definition, explanation and
  demonstration of "confounding" in fractional
  factorial designs.

5
(5) The benefits of DOE are compared with the
traditional one-factor-at-a-time (OFAT)
designs. (6) The concept of using center points
in two-level designs is rigorously explained and
demonstrated. (7) Normal and half-normal
probability plots are explained and illustrated
by example or in-class exercise. (8)
Plackett-Burman screening designs are introduced
and explained, and contrasted with traditional
fractional factorial designs.
6
(9) The concept of "foldover designs" is
introduced and explained. (10) Mixture designs
are briefly explained. (11) The technique known
as the "method of steepest ascent" is introduced
and explained. (12) The advanced topic of
"response surface methodology" (RSM) is
introduced by way of lecture. Total time
allocated to RSM should not exceed two to three
hours.
7

• The resulting course content is captured in the
  illustration, next page, which partitions the
  various course topics into four areas that mimic
  the Deming PDCA cycle
• Planning (pre-experimental), (15)
• Design (types), (30)
• Conduct (of an experiment), (20)
• Analysis (of the data). (35)

8
(No Transcript)
9

• During course development, I identified ten key
  concepts or pedagogical best practices associated
  with a DOE course they are listed below.

• Students should have at least one team exercise
  early in the course where they use their
  "pre-course" knowledge to plan and execute an
  in-class experiment. This experience then serves
  as motivation to learn the new DOE methodology.
• Because variation is a researcher's relentless
  enemy, the course should emphasize issues
  involving variability blocking, randomization,
  measurement error, recording error, bias,
  confounding, residual plots, analysis of
  variance, etc.
• Experimentation should be sequential. Emphasize
  that no more than 25 percent of one's research
  budget should be spent on the first experiment.

10

• Multiple responses are a fact of life in today's
  complex world. Students should be shown how to
  simultaneously optimize a process involving more
  than one response variable.
• Software is essential for DOE no one does
  calculations by hand.
• Two-level designs are the workhorse of DOE. At
  least half of the course schedule should be
  devoted to them.
• A transformation of the response variable is
  occasionally required. This is an advanced topic.
  
• Students should be introduced to the idea of
  transformations and when they might be needed,
  appropriate or essential.

11

• Sample size matters a lot. Students should be
  shown how to estimate the sample size required to
  detect an effect of a given size for a two-level
  factorial at various confidence (or, 1) levels
• Taguchi's concepts of variance reduction and
  robust design are not only important from a
  pedagogical standpoint they are considered a
  best practice for a world-class DOE course.
• Students must learn how to explain their
  experimental results in the context of management
  briefings without using DOE jargon and buzzwords.

12
2. Teaching Skill Outstanding teachers
are truly valuable human beings, more so
because they are rare.

• A prospective DOE instructor should provide
  copies of student evaluations of his/her teaching
  of the DOE course under consideration. Evaluation
  forms (or rating scores) from all former students
  should be included to prevent biased reporting.
• A prospective DOE instructor should provide the
  names, addresses and phone numbers of at least
  two references who took his/her course, and who
  are willing to comment on its content and the
  quality of instruction.

13

• Managers should have at their disposal
  information relating to teaching skill from one
  or more of the following sources student
  evaluations, reference checks, and/or course
  audits.

• With this information, it should be possible to
  effectively evaluate a course and its instructor
  using the following criteria
• The instructor's demonstrated subject-matter
  knowledge
• The instructor's demonstrated ability to respond
  effectively to student questions and comments
• The instructor's demonstrated ability to present
  information and concepts effectively
• The manager's overall assessment of the
  instructor's effectiveness as an educator.

14
3. Course Materials Essential course
materials for a world-class introductory
DOE course

• Student Textbook
• Course Notes
• Supplemental Readings
• Design Toolkit
• DOE Software

15
Student textbook
Only a few of the benchmarked courses provided a
student text as part of the course offering.
Students should be provided with an exemplary
textbook to keep after the course is over.
Course notes
It has been claimed that 80 percent of learning
occurs through the sense of sight . If true, this
means that the use of overhead slides by the
instructor can be a significant improvement over
pure lecture without notes. Distribute copies of
the instructor's lecture slides or overheads at
the beginning of class, to facilitate notetaking.
16
Supplemental readings
Provide students with a useful and extensive
selection of easy-to-understand journal articles
relevant to the subject of experimental design.
Design toolkit
Provide students with an extensive collection of
useful design tools/aids that simplify the design
of an experiment and the analysis of data.
DOE software
Consider introducing any in-class activity
designed to reduce student anxiety typically
associated with mathematics, statistics, and
computation.
17
4. In-Class Experiments
With regard to in-class experiments, students
should work alone, or preferably in small groups
of three to five, to generate and analyze their
own experimental data during class. Consider the
use of one or more video presentations in class
to present course material in an interesting and
informative way.
18
5.DOE Software
Students should be provided with user-friendly
DOE software during the course for analyzing
data.
Students should be provided a free personal copy
of the course software for use upon their return
to work.
19
6. Integration with Other TQM Tools
Two additional tools-flow charting and
cause-and-effect diagrams-tend to be used
together to solve problems. The flow chart
documents the actual step-by-step process used in
the conduct of an experiment the
cause-and-effect diagram is a vehicle for
brainstorming actions that can be taken to reduce
variation in each step on the flow chart.
20
7. Select Taguchi Methods
Taguchi introduced the concept of robust design,
which is a simple experimental design methodology
that attempts to make products and processes
insensitive to the degradation posed by
uncontrollable factors (noise) in the
environment.
Any world-class DOE course should explain or
illustrate Taguchi's approach to identifying
variance-reducing factors.
21
In Conclusion
DOE is an important methodology for any company
involved in product or process development. It is
becoming increasingly difficult to compete in a
global economy without the use of this and other
select performance-enhancing tools. Considering
that a firm's technical staff consists of some of
the highest paid individuals on the payroll,
their time and talents are too valuable to waste
by sending them to less than stellar courses and
workshops.
The End