Inference in an Authorship Problem

Abstract This study has four purposes: to provide a comparison of discrimination methods; to explore the problems presented by techniques based strongly on Bayes' theorem when they are used in a data analysis of large scale; to solve the authorship question of The Federalist papers; and to propose routine methods for solving other authorship problems. Word counts are the variables used for discrimination. Since the topic written about heavily influences the rate with which a word is used, care in selection of words is necessary. The filler words of the language such as an, of, and upon, and, more generally, articles, prepositions, and conjunctions provide fairly stable rates, whereas more meaningful words like war, executive, and legislature do not. After an investigation of the distribution of these counts, the authors execute an analysis employing the usual discriminant function and an analysis based on Bayesian methods. The conclusions about the authorship problem are that Madison rather than Hamilton wrote all 12 of the disputed papers. The findings about methods are presented in the closing section on conclusions. This report, summarizing and abbreviating a forthcoming monograph 8, gives some of the results but very little of their empirical and theoretical foundation. It treats two of the four main studies presented in the monograph, and none of the side studies.