On Sentence-Length as a Statistical Characteristic of Style in Prose: With Application to Two Cases of Disputed Authorship

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Abstract

ONE element of style which seems to be characteristic of an author, in so far as can be judged from general impressions, is the length of his sentences.This author develops his thought in long, complex and wandering periods: that finds sufficient for his purpose a sequence of sentences that are brief, clear and perspicuous.Since the length of a sentence can be readily measured, for practical purposes, by the number of words, it occurred to me that it would be of interest to subject this impression to statistical investigation.In carrying out the investigation, I met with more difficulties than I had foreseen.There are two terms used above: (1) Sentence, (2) Word.What is a sentence?What is a word, or what for present purposes is to be regarded as a word?Sentence.Let me cite the New English Dictionary: SENTENCE.Ab. 6.A series of words in connected speech or writing, forming the grammatically complete expression of a single thought; in popular use often ( = Period sb.10) such a portion of a composition or utterance as extends from one full stop to another.In Grammar, the verbal expression of a proposition, question, command, or request, containing normally a subject and a predicate (though either of these may be omitted by ellipsis).In grammatical use, though not in popular language, a sentence may consist of a single word.... English grammarians usually recognize three classes: simple sentences, complex sentences (which contain one or more subordinate clauses), and compound sentences (which have more than one subject or predicate).From these definitions I conclude, I hope rightly, that we may drop the term 'period" and use the term "sentence" to cover any sentence (or as I should have been inclined to write " period ",), however complex and however compound in the senses defined.It is convenient to be able to avoid a term which to a statistician would generally suggest a different meaning.Now, not being a grammarian but just one of the populace, I confess that I started with the popular notion of a "sentence" in this general sense: "such a portion of a composition as extends from one full stop to another", and thought I would have nothing to do but tot up the words from full stop to full stop.The first definition, however, reads: "the grammatically complete expression of a single thought."I feel some doubts as to the "single thought". (Is not "I am tired and hungry" a sentence, and does it not convey two thoughts, the thought of being tired and the thought of being hungry?)But the " grammatically complete