This program works by counting the words in a text that occur in the Academic Word List, a list of the most commonly found words in academic texts which are not among the 2,000 most common words in general English. For example, "analyse" scores a hit, while "go" does not.
The AWL is divided into sublists, with Sublist 1 containing the most common words, and Sublist 10, the least. We can guess, then, that a text which scores higher on Sublist 10 than Sublist 1 may be somewhat obscure, but this is only a guess.
The overall score (the first bar) is a rough guide to how "academic" a text is. However, it should be treated with a pinch of salt. Very short texts can give a misleading result (for example, I entered my e-mail sig file, and it went off the scale). It is also possibly that an academic text may contain a large number of obscure words that are not in the AWL (e.g. "deconstruction", "quasar"), and thus give the impression that it is less "academic" than the average paper.
The program will also comment on the level of the text: "erudite", "academic", "literate" or "colloquial". These comments should not, however, be taken too seriously; they are simply generated by comparing the ratio of words in the AWL to common words (found in the General Service List).
To give a rough idea of what the overall scores mean, here are some texts that have been processed, with the AWL words-per-thousand count.
Text | Text type | Common word count | AWL word count | Comment generated |
CGI.pm - a Perl Library | Technical documentation | 579 | 270 | Erudite |
Mandrake RPM Howto | Technical documentation | 636 | 200 | Erudite |
Olsen et al.: "Dynamics of Trapped Bose-Einstein Condensates" | Academic paper (physics) | 564 | 150 | Erudite |
Ovunc Gurbuz: "Different views on Happiness" | Student essay (English 101) | 659 | 100 | Academic |
Robin Turner: "Some Semantic and Cognitive Aspects of Desire" | Academic paper (philosophy) | 771 | 91 | Academic |
Aron Ahuvia: "Individualism/Collectivism and Cultures of Happiness" | Academic paper (sociology) | 576 | 90 | Academic |
Kevin Dunn: "Representing Counsel" | Academic paper (literature) | 629 | 66 | Literate |
David Weber: "1633" (first chapter) | Historical novel | 721 | 61 | Literate |
Buffy the Vampire Slayer (first episode) | TV script | 721 | 20 | Colloquial |
Back to the Future | Film transcript | 743 | Less than 1 | Colloquial |
Note how technical writing often appears more "academic" than academic papers, and how students may sometimes score higher than academics (possibly because they are consciously trying to use academic vocabulary).