building a better twinkie a mixture design problem katherine l. monti, ph.d. r principal statistical...
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Building a Better Twinkie—
A Mixture Design Problem
Katherine L. Monti, Ph.D.r
Principal Statistical Scientist, Rho, Inc. k
March 12, 2011
Why Statistics? Why Biostatistics?
• Math • Earning power $ $ $ was not in math
• Variety of non-math courses
• Math + Applications Statistics
• Forestry, biology, education, anthropology, finance and economics, sociology, manufacturing, advertising, ….
• Epidemiology, health sciences, medicine, drug development,
Where I’ve Been and Why
• UNC Sch. of Public Health -- Chapel Hill • University of Missouri - St. Louis
Department of Mathematics & Computer Science
• Ralston Purina Company
• Ciba Corning Diagnostics Corporation
• Astra Pharmaceuticals
• Rho, Inc.• Along the way – a little independent consulting
I wanted variety
• I got variety!
• Some of the projects I’ve worked on over the decades.
Projects
• Energy review system (Ralston) – Simple review of energy usage, external temperature, and
production saved millions of dollars a year per plant
Energy use = a + b (external temperature) + c (tons*)
* Tons of pet food or cereal produced
Projects• Effects of weight gain restriction in Labrador retrievers
(Ralston): DG448—only long-term, large mammal study investigating the health and longevity advantages of lean body mass (achieved in dogs by diet restriction)
Projects
• Feline reproduction (Ralston): a publication of simple summary of data from Ralston cattery has become a classic paper in veterinary medicine
Projects
• Heritability of feline cardiomyopathy: 25 years of feline reproductive data, 7 generations of ancestors (27 = 128)
– MMMMMMM - MMMMMM …. - MM - M
– MMMMMMF - MMMMMF - MF - F
– MMMMMFM - MMMMFM - FM
– MMMMMFF - MMMMFF - FF
– MMMMFMM …
– MMMMFMF - FFFFFF
– MMMMFFM
– …
– FFFFFFF
Projects
• Salary discrimination law suit (Independent consulting)
– Fauteck vs Montgomery Ward, 1970’s and early ‘80s
– Systematically paid women less
• In general, women had more years of experience, longer time with the company, higher education…and a lower salary, for any job category
– ~ $5,000,000 settlement
Projects
• Medical instrumentation (Ciba Corning)
– Blood gas machines
– Co-oximeters
– PSA testing
Projects
• Drug studies (Astra, Rho): blood pressure, acute pain, chronic pain, kidney disease, Alzheimer’s, opioid-induced constipation, asthma, allergy, AIDS, autism, cancer, traumatic brain injury, arthritis, diabetes….
Twinkies
• Studying the ratio of emulsifiers in Hostess Twinkies for optimal springiness (Ralston/Continental Baking)– A mixture design– 3 emulsifiers make up a total of 5% of the recipe– How to decide the proportions of the emulsifiers
Statisticians Have Variety• Opportunities exist in many fields
• So....you can find one you like and go in that direction
It is a great time to be a biostatistician!
• http://www.biostatpharma.com
• Google “biostatistics” “prospective student”
When I graduated, I had no idea...
• How much writing I would do and how valuable my high school grammar class would be.
• That I should have taken more chemistry.
• How important team work is.
When I graduated, I had no idea...
• How much the field of statistics would continue to grow.
• How much you teach even when you don’t teach.
• How valuable curiosity, common sense, and common courtesy are.