If a noun is usually in the plural, or a verb is usually in the passive, this is a salient fact about the word (possibly worth mentioning in a dictionary). We include these facts in the word sketch in the form of word sketch highlights. 75% of the occurrences of the English noun constraint in the BNC are in the plural. How salient is this fact? To answer, we need to know whether it is unusual or typical behaviour for an English noun. We need to assess the fact about constraintagainst the background of “other nouns”.
We do this by
- calculating the percentage for all nouns,
- putting them in rank order, and
- seeing whether the keyword (e. g., constraint) is an exceptional case.
If it is, we add a note to the word sketch — we simply decide if the percentage of the word occurring in plural exceeds a pre-specified threshold. Default value for “what counts as noteworthy” (so that we add a note to the word sketch): in the highest 10% of the population.
The approach is currently being tested: parameters will probably change.