Using compression to identify acronyms in text

Abstract

Summary form only given. Finding acronyms and their definitions in free text is useful for many purposes. We have developed a new method that uses several PPM models to encode the acronym in terms of its definition. Four different attributes of each acronym are encoded using a PPMD order 5 model: (a) whether the acronym occurred before or after its definition (direction); (b) the distance between the acronym and the definition (first-word offset); (c) the pattern of words in the definition with letters in the acronym (subsequent-word offsets); and (d) the number of letters taken from each of those words. These models, taken together, give a complete encoding of the acronym in terms of its definition. The models were trained on 1080 acronyms extracted from 150 documents. A model of plain text was trained using 100 independent documents from the same collection.