statistical challenges and opportunities in the
TRANSCRIPT
Statistical Challenges and Opportunities in the
Semiconductor Industry
Joel Dobson
Texas Instruments
Pstat®
A chronology of buzz words
Laplace! Bayes.
Statistician (& Mark Twain’s quote, Fisher)
Total Quality Management
Six Sigma Black Belt, ISO, TS,…
Data mining
Thinking statistically
Big data, Data scientist
What next? Distributed computing, cloud,
Hadoop®, Google tools®…..
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Images from: Wikipedia web page and Amazon web page.
Thinking Statistically & Statistical Engineering
Started by Dr. Roger Hoerl formerly of GE now at Union College, Dr. Ron D. Snee, and others
• Variation exists
• Maybe more than one
variance, or mixed models
• Continuous Y versus categorical Y
Line on a scatter plot,
box plots, ROC curves, …
• Paired data or not? Longitudinal?
Repeated measures.
• Risk as an average loss or an average utility
• Converting prior information into posterior
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Image from: Google image search for “Hoerl and Snee” at SAS Institute.
Our role in the SC industry
We do not need to invent much. (But can)
Be aware and use what exists.
But, be sure to enjoy!
What can go wrong?
Don’t like the original CPK definition? Just redefine it….
Perhaps most dangerous? --- Type IV errors
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The four errors
One is reject the null when true.
Two is to NOT reject the null when false.
Three is answering the wrong question well.
Four is using a deeper method than needed.
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Our role in the SC industry
Beware of the democratization of statistics.
By analogy to medical practice…
The skills must be appreciated on both sides.
Jargon is a two way street. Learn device physics.
15 Images from: 1.mediabistro.com, 2. http://lotsasplainin.blogspot.com/ and 3. publicoccurrenc.blogspot.com
Sematech Statistical Council (SSC)
• Sematech in Austin
• Yearly Fall Conference
• One of the parallel sessions
• Attrition of statisticians at Sematech
• The work with regard to AIAG books
• Applied Reliability by
Tobias and Trindade
• NIST Statistics Handbook
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Image from: 1. Google image search and 2. from a personally shared photo.
Differentiating yourself as a PStat
• You cannot be passive! Was Steve Jobs?
• Sell your skills widely. Set a marketing plan. Blog!
• Get to know your IT & corporate communications people!
• Make videos when teaching. Didactic pedagogy.
• Innovate then give presentations, but target your pitch to your audience.
• Be able to explain in terms of finance: revenue or profit.
• Service and standards outside your company.
• Seek patents every chance you get.
• Consider yourself lucky to help others. Enjoy and thrive.
• Mutual admiration, opportunity abounds, fame
• Optimism is a muscle. ( Robin Roberts quote )
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Hierarchical
We may have several variances.
Fabs: lots, wafers, chips, cross to tools or batches
Assembly and test sites: (AT)
AT lots, chips, and then cross to fab lot.
Tester, Handler, Loadboard, Test Site (quadsite, etc)
The bivariate tests may be inappropriate.
Do not take sample sizes from a bivariate test.
Much harder with >1 variance! (Brendler, IBM)
Random effects models or mixed models.
The whole censored data topic.
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Engineering Significance
• Some call this “Meaningfulness”.
• Practicality?
• For example, two processes may be statistically significantly different in the mean but the difference is practically meaningless.
• Correlation…
Picture from Linked In’s Kevin Anderson site.
Statistical Software (one example)
Excel®
JMP® or Minitab®
R® or other for scripting
Home grown ETL
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Recent Excitement
The world is our oyster right now!
Best jobs ----- USA Today 4/19
1. Mathematician,
2. Tenured Professor,
3. Statistician,
4. Actuary
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http://www.usatoday.com/story/money/business/2014/04/19/cnbc-best-and-worst-jobs-of-2014/7881247/
Recent Excitement
Medical clinical trials: Sequential methods, ethical concerns Human genome (HGP®: Craig Ventner, Francis Collins now leads the NIH in DC) Better hazard methods Open BUGS® Better predictions Repeated measures Time structures of covariance (ARIMA)
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Join Us !! MOOCs online. Just Google search ‘MOOC’ or ‘MOOC Statistics’.
Get on to various monthly newsletter list. (inside and outside)
Take CE courses: { ASA JSM, R, JMP, DOE, other }
Local R Users group third Saturdays at 10 at U of D near DFW airport
Weekly seminars. SMU in Stats and at UTD in Stats. Free.
Local ASA – Dallas Monthly ASA meeting at SMU third Thursday at 7 pm.
Brad Efron was here on 2/27 at SMU as the first Schucany lecture.
Many RSS feeds from statistical blogs.
Use Feedly reader to find them, or any other topic.
Follow us or connect on Linked In.
29 Images from: zimbio.com/pictures after a Google image search, and SMU Dedman School web page