Stats is of course not just about numbers, it’s also often used to analyse words, even more so now with the explosion of social media in the past few years. But the late great Phil Stone of Harvard University’s General Inquirer for the quantitative analysis of text was developed in the early 1960’s. A few years later, in 1964, the release of the Ford Mustang and the Pontiac GTO pony/muscle cars, the late great Fred Mosteller and the great (and still with us) David Wallace published their book on the (mainly) Bayesian analysis of who wrote the Federalist Papers, a year after an introductory paper had appeared in the Journal of the American Statistical Association.
In the late 18th Century, three key figures in the foundation of the United States – Alexander Hamilton, John Jay and James Madison wrote 85 newspaper articles to help ratify the American Constitution.
The papers were published anonymously, but scholars had figured out the authorship of all but twelve, not knowing for sure whether these had been written by Madison or Hamilton. The papers were written in a very formal, and very similar, style,and so Mosteller and Wallace turned to function words like “an” and “of” and “upon and particularly “while” and “whilst”, a researcher from back in 1916 having noticed that Hamilton tended towards the former, Madison the latter. Computers back in the 60’s were pretty slow, and expensive, and hard to come by, there weren’t any at Harvard, where Mosteller had recently established a Statistics Department, and so they had to use the one at MIT.
In Mosteller and Wallace’s own words, after the combined work of themselves and a huge band of helpers, they “tracked the problems of Bayesian analysis to their lair and solved the problem of the disputed Federalist papers” using works of known authorship to conclude that Madison wrote all 12.
In 1984, M & W published a newer edition of their groundbreaking, and highly readable book with a slightly different title, while a few years later, the late great Colin Martindale (with a Harvard doctorate) and myself re-analysed the original data using Stone’s General Inquirer thematic dictionary as well as function words, and a type of kernel discriminant analysis / neural network, coming to the same conclusion.
Case closed? Not quite. It has recently been proposed that the disputed 12 papers were a collaboration, a summary of the evidence, and some other citations to classical & recent quantitative Federalist research are available here
http://www.dh2012.uni-hamburg.de/conference/programme/abstracts/the-twelve-disputed-federalist-papers-a-case-for-collaboration/
Either way, when you’re getting a bit jaded with numbers, and the 0’s are starting to look like o’s, analyse text!
Further/Future reading
Mosteller F, Wallace DL (1964) Inference and disputed authorship, the Federalist. Addison-Wesley.
McGrayne, SB (2011) The theory that would not die: how Bayes’ rule cracked the Enigma code, hunted down Russian submarines & emerged triumphant from two centuries of controversy. Yale University Press.
Martindale C, McKenzie D (1995) On the utility of content analysis in author attribution: The Federalist. Computers and the Humanities, 29, 259-270.
Stone PJ, Bales RF, Namenwirth JZ, Ogilvie DM (1962). The General Inquirer: a computer system for content analysis and retrieval based on the sentence as a unit of information. Behavioral Science, 7, 484-498.
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