The Matrixx Oversold

“Now their view is the rule of law: Statistical significance is neither necessary nor sufficient for proving a commercial or scientific result.”

Statistics Experts

The perverse rhetorical distortions of the Matrixx case have begun.  The quote above, from the website of one of the amicus brief authors, will probably not be the last distortion or perversion of scientific method or of the holding of Matrixx Initiatives, Inc. v. Siracusano, 2011 WL 977060 (March 22, 2011, U.S. Supreme Court).  Still, the distortion of the holding raises some interesting questions about who these would-be friends of the Court are, and why would they misrepresent the case in a way that any first-year law student would see was incorrect.  What is the agenda of these authors?

I had never heard of Deirdre N. McCloskey or Stephen T. Ziliak before the Matrixx case.  After the decision was delivered on March 22, 2011, I started to look at the amicus briefs.  McCloskey and Ziliak filed one such brief, on behalf of the respondents.  Their brief was styled “Brief of Amici Curiae Statistics Experts Professors Deirdre N. McCloskey and Stephen N. Ziliak in Support of Respondents.”  The more I considered this amicus brief, the more troubling I found it, both procedurally and substantively.

1. No statistical organization (such as the American Statistical Association) joined this amicus brief, and none of the many statistician-lawyers who frequently contribute amicus briefs on quantitative issues was associated with their effort.  This was the first peculiarity of the McCloskey-Ziliak brief, which attracted my attention only after the Supreme Court issued its opinion in the Matrixx case.

2. The second remarkable fact about these amici is that they are not statisticians or statistics professors, despite titling their brief as that of “statistics experts.”  According to his website, Stephen T. Ziliak, is a Professor of Economics,in the department of economics, in Roosevelt University (Chicago). His doctorate was in economics.  Deirdre N. McCloskey is a professor of economics, history, English, and communication, at the University of Illinois (Chicago).  Of course, this is not to say that these professors do not have expertise in statistics.  Both authors have written on the history of statistics, but the title of their brief seems a bit misleading.  Why would they not say that they were economists?  I, for one, found this ruse peculiarly misleading for a brief filed in our highest Court.

3. The third curious fact is the incestuous nature of the brief’s authors.  McCloskey was Ziliak’s doctoral supervisor. Again, there is nothing wrong with a mentor and his or her student joining together in a project such as this, but the work suggests an intellectual inbreeding, which was, well, peculiar in that no one else with putative substantive expertise was involved in the amicus brief.

4.  Some of the McCloseky-Ziliak brief is unexceptional exposition about the meaning of Type I and Type II errors, and hypothesis testing.  The Supreme Court really did not need this information, which could readily be found in the Federal Judicial Center’s Reference Manual on Scientific Evidence.  Some of the brief, however, is peculiarly tendentious nonsense, which I will explore in follow-up posts.

5. The Supreme Court, in its opinion, did not dignify this amicus brief with a citation, but the amici nonetheless appear to have a delusionally inflated view of their influence.  Now there is nothing at all peculiar about such delusions in academia.  A short trip to Ziliak’s and McCloskey’s websites revealed many references to their efforts on the brief, including their (inflated) assessment of their influence. McCloskey’s website goes further, with what appears to be a press release, in which she claims, without citation or support that some of “their book and some of their articles did affect the case.”

6. The press release ends with the harrumphing, noted above:

“Now their [McCloskey and Ziliak’s] view is the rule of law: ‘Statistical significance is neither necessary nor sufficient for proving a commercial or scientific result.””

This statement, of course, is not the rule of law; nor is it the holding of the case.  The statement is so clearly wrong that the reader has to wonder about the authors’ academic pretenses, qualifications, and claimed disinterest in the proceedings.  Rhetorical excess is no stranger in the halls of academia, but our learned professors appear to have jumped the rhetorical shark.

This amicus brief certainly got my attention, and it raises serious questions about who files amicus briefs, and whether they distort the appellate process.   In a follow-up post, I will look at some of the substantive opinions put forward by McCloskey and Ziliak.  Like the curious distortions of their credentials, the  misleading assessment of their own influence, and the erroneous conclusion about the Matrixx holding, the substantive claims and statements by these authors, in their amicus brief, are equally dubious.  Their claims are worth exploring as a road map to how other irresponsible advocates may use and misuse the Matrixx.