While at University of Iowa, he served as resident scholar in the Project on Rhetoric of Inquiry, where he met among others Steve Fuller, Bruno Latour, and Wayne C. Booth, and co-authored the now-famous paper "The Standard Error of Regressions".
[10] After college, but prior to his academic career, Ziliak served as county welfare caseworker and, following that, labor market analyst for the Indiana Department of Workforce Development, both in Indianapolis.
[11] In their paper, "The Standard Error of Regressions," McCloskey and Ziliak argue that econometrics greatly over-values and vastly misuses statistical significance testing — Student's t-test.
In a reply to critics, Ziliak and McCloskey did a follow-up study of the 1996 research and found that the significance problem had grown even larger, causing false inferences and decisions in from 70% in the 1980s to 80% of the 1990s articles published in the American Economic Review.
[6] The article and a reply to critics ("Significance Redux") were published in a special issue of the Journal of Socio-Economics, with comments from Nobel laureate Clive Granger, Arnold Zellner, Edward Leamer, Gerd Gigerenzer, Jeffrey Wooldridge, Joel Horowitz and a half dozen others.
Try Gosset's Guinnessometrics When a Little 'p' Is Not Enough" was published in a follow-up special issue of The American Statistician (2019 73 sup1), a major re-think of statistical testing, estimation, and reporting in "A world beyond p<0.05" for which Ziliak also served as associate editor.
His book, The Cult of Statistical Significance: How the Standard Error Costs Us Jobs, Justice, and Lives (2008) challenges the history, philosophy, and practice of all the testing sciences, from economics to medicine, and has been widely reviewed in journals and the media.
[17][18][19][20][21][22][23][24][25] It was the beer-brewing Gosset aka "Student", Ziliak discovered in the archives, not the biologist R. A. Fisher, who provided the firmer foundation for modern statistics, decisions, and experimental design.
The book featured in a 2011 U.S. Supreme Court case, Matrixx Initiatives v. Siracusano et al., wherein the justices unanimously decided against using statistical significance as a standard for adverse event reporting in U.S. securities law.
In 2008 and 2009 Ziliak's work on haiku economics gained international attention following a series of articles published in the Wall Street Journal, The Economist, The Chronicle of Higher Education, and National Public Radio.
[39][41] Ziliak's Guinnessometrics was twice featured on BBC Radio 4's "More or Less" program, hosted by Tim Harford, and later in many other media such as The Wall Street Journal Europe, Financial Times, Salon and The Washington Post.
Validity is proven by other means, including deliberately balanced and stratified experiments, small series of independent and repeated samples controlling for real not merely random error, and an economic approach to the logic of uncertainty.
[44][45][46][47] In July 2008 Ziliak was invited by the International Biometric Society and the Irish Statistical Association to present his work in Dublin on "Guinnessometrics: The Economic Foundation of Student's t," in celebration of the 100th anniversary of W.S.
[48] Standing on stage with Sir David Cox and Stephen Senn, the biostatistician and president of the American Statistical Association Chicago Chapter Borko Jovanovic quipped that Ziliak "looked, at first, like a little kid walking around the British Museum.
In his 2011 essay on "Haiku Economics," published in Poetry magazine, Ziliak noted the influence of Adam Smith's The Theory of Moral Sentiments and John Stuart Mill's Autobiography.