Monthly Archives: May 2014

What have we learned from the Anil Potti training and test data fireworks ? Part 1 (draft 2)

toilet-fireworks-by-stephenthruvegas-on-flickr

Over 100 patients signed up for the chance to participate in the clinical trials at Duke (2007-10) that promised a custom-tailored cancer treatment spewed out by a cutting-edge prediction model developed by Anil Potti, Joseph Nevins and their team at Duke. Their model purported to predict your probable response to one or another chemotherapy based on microarray analyses of various tumors. While they are now described as “false pioneers” of personalized cancer treatments, it’s not clear what has been learned from the fireworks surrounding the Potti episode overall. Most of the popular focus has been on glaring typographical and data processing errors—at least that’s what I mainly heard about until recently. Although they were quite crucial to the science in this case,(surely more so than Potti’s CV padding) what interests me now are the general methodological and logical concerns that rarely make it into the popular press. Continue reading

Categories: science communication, selection effects, Statistical fraudbusting

Allan Birnbaum, Philosophical Error Statistician: 27 May 1923 – 1 July 1976

27 May 1923-   1 July 1976

Today is Allan Birnbaum’s Birthday. Birnbaum’s (1962) classic “On the Foundations of Statistical Inference” is in Breakthroughs in Statistics (volume I 1993).  I’ve a hunch that Birnbaum would have liked my rejoinder to discussants of my forthcoming paper (Statistical Science): Bjornstad, Dawid, Evans, Fraser, Hannig, and Martin and Liu. I hadn’t realized until recently that all of this is up under “future papers” here [1]. You can find the rejoinder: STS1404-004RA0-2. That takes away some of the surprise of having it all come out at once (and in final form). For those unfamiliar with the argument, at the end of this entry are slides from a recent, entirely informal, talk that I never posted, as well as some links from this blog. Happy Birthday Birnbaum! Continue reading

Categories: Birnbaum, Birnbaum Brakes, Likelihood Principle, Statistics

Blog Table of Contents: March and April 2014

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BLOG Contents: March and April 2014
Compiled by Jean Miller and Nicole Jinn

March 2014

(3/1) Cosma Shalizi gets tenure (at last!) (metastat announcement)

(3/2) Significance tests and frequentist principles of evidence: Phil6334 Day #6

(3/3) Capitalizing on Chance (ii)

(3/4) Power, power everywhere–(it) may not be what you think! [illustration]

(3/8) Msc kvetch: You are fully dressed (even under you clothes)? Continue reading

Categories: blog contents

The Science Wars & the Statistics Wars: More from the Scientism workshop

images-11-1Here are the slides from my presentation (May 17) at the Scientism workshop in NYC. (They’re sketchy since we were trying for 25-30 minutes.) Below them are some mini notes on some of the talks.

Now for my informal notes. Here’s a link to the Speaker abstracts;the presentations may now be found at the conference site here. Comments, questions, and corrections are welcome. Continue reading

Categories: evidence-based policy, frequentist/Bayesian, Higgs, P-values, scientism, Statistics, StatSci meets PhilSci

Deconstructing Andrew Gelman: “A Bayesian wants everybody else to be a non-Bayesian.”

At the start of our seminar, I said that “on weekends this spring (in connection with Phil 6334, but not limited to seminar participants) I will post some of my ‘deconstructions of articles”. I began with Andrew Gelman‘s note  “Ethics and the statistical use of prior information”[i], but never posted my deconstruction of it. So since it’s Saturday night, and the seminar is just ending, here it is, along with related links to Stat and ESP research (including me, Jack Good, Persi Diaconis and Pat Suppes). Please share comments especially in relation to current day ESP research. Continue reading

Categories: Background knowledge, Gelman, Phil6334, Statistics

Scientism and Statisticism: a conference* (i)

images-11A lot of philosophers and scientists seem to be talking about scientism these days–either championing it or worrying about it. What is it? It’s usually a pejorative term describing an unwarranted deference to the so-called scientific method over and above other methods of inquiry. Some push it as a way to combat postmodernism (is that even still around?) Stephen Pinker gives scientism a positive spin (and even offers it as a cure for the malaise of the humanities!)[1]. Anyway, I’m to talk at a conference on Scientism (*not statisticism, that’s my word) taking place in NYC May 16-17. It is organized by Massimo Pigliucci (chair of philosophy at CUNY-Lehman), who has written quite a lot on the topic in the past few years. Information can be found here. In thinking about scientism for this conference, however, I was immediately struck by this puzzle: Continue reading

Categories: Announcement, PhilStatLaw, science communication, Statistical fraudbusting, StatSci meets PhilSci | Tags:

Who ya gonna call for statistical Fraudbusting? R.A. Fisher, P-values, and error statistics (again)

images-9If there’s somethin’ strange in your neighborhood. Who ya gonna call?(Fisherian Fraudbusters!)*

*[adapted from R. Parker’s “Ghostbusters”]

When you need to warrant serious accusations of bad statistics, if not fraud, where do scientists turn? Answer: To the frequentist error statistical reasoning and to p-value scrutiny, first articulated by R.A. Fisher[i].The latest accusations of big time fraud in social psychology concern the case of Jens Förster. As Richard Gill notes:

The methodology here is not new. It goes back to Fisher (founder of modern statistics) in the 30’s. Many statistics textbooks give as an illustration Fisher’s re-analysis (one could even say: meta-analysis) of Mendel’s data on peas. The tests of goodness of fit were, again and again, too good. There are two ingredients here: (1) the use of the left-tail probability as p-value instead of the right-tail probability. (2) combination of results from a number of independent experiments using a trick invented by Fisher for the purpose, and well known to all statisticians. (Richard D. Gill)

Continue reading

Categories: Error Statistics, Fisher, significance tests, Statistical fraudbusting, Statistics

A. Spanos: Talking back to the critics using error statistics (Phil6334)

spanos 2014

Aris Spanos’ overview of error statistical responses to familiar criticisms of statistical tests. Related reading is Mayo and Spanos (2011)

Categories: Error Statistics, frequentist/Bayesian, Phil6334, reforming the reformers, statistical tests, Statistics

Winner of April Palindrome contest: Lori Wike

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Lori Wike

Winner of April 2014 Palindrome Contest:

Lori Wike

Palindrome:

Pose ad: ‘Elba fallacy amid aged? Amygdala error or real?’ Ad: gym ad? Egad! I may call a fabled Aesop.

The requirement: A palindrome with Elba plus “fallacy” with an optional second word: “error”. A palindrome using both topped an acceptable palindrome using only “fallacy”. All April submissions used both. Other April finalists are here.

Bio:

Lori Wike is principal bassoonist of the Utah Symphony and is on the faculty of the University of Utah and Westminster College. She holds a Bachelor of Music degree from the Eastman School of Music and a Master of Arts degree in Comparative Literature from UC-Irvine.

Continue reading

Categories: Announcement, Palindrome

You can only become coherent by ‘converting’ non-Bayesianly

Mayo looks at Bayesian foundations

“What ever happened to Bayesian foundations?” was one of the final topics of our seminar (Mayo/SpanosPhil6334). In the past 15 years or so, not only have (some? most?) Bayesians come to accept violations of the Likelihood Principle, they have also tended to disown Dutch Book arguments, and the very idea of inductive inference as updating beliefs by Bayesian conditionalization has evanescencd. In one of Thursday’s readings, by Baccus, Kyburg, and Thalos (1990)[1], it is argued that under certain conditions, it is never a rational course of action to change belief by Bayesian conditionalization. Here’s a short snippet for your Saturday night reading (the full paper is https://errorstatistics.files.wordpress.com/2014/05/bacchus_kyburg_thalos-against-conditionalization.pdf): Continue reading

Categories: Bayes' Theorem, Phil 6334 class material, Statistics | Tags: ,

Putting the brakes on the breakthrough: An informal look at the argument for the Likelihood Principle

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Friday, May 2, 2014, I will attempt to present my critical analysis of the Birnbaum argument for the (strong) Likelihood Principle, so as to be accessible to a general philosophy audience (flyer below). Can it be done? I don’t know yet, this is a first. It will consist of:

  • Example 1: Trying and Trying Again: Optional stopping
  • Example 2: Two instruments with different precisions
    [you shouldn’t get credit (or blame) for something you didn’t do]
  • The Breakthough: Birnbaumization
  • Imaginary dialogue with Allan Birnbaum

The full paper is here. My discussion takes several pieces a reader can explore further by searching this blog (e.g., under SLP, brakes e.g., here, Birnbaum, optional stopping). I will post slides afterwards.

Mayo poster

Categories: Announcement, Birnbaum Brakes, Statistics, strong likelihood principle

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