הגדרות
Aboutness – not limited to the keywords from the text. The overall purpose, scope and audience should be understood then an understanding of the specific aspects and their relation to the whole. Theres a difference between what the words say and what they mean. Basically all language is vague, so computers are poor indexers. Index needs to discriminate btwn major and minor topics. Often the text itself isn’t clear about this. Specificity- the extent to which a topic is identified by a precise term. The more specific the term, the more precise the results. More generic terms will bring up more terms than are necessary. Good idea is to index according to the specificity of the author. Don’t move content analysis away from the document by adding more terms. exhaustivity – implies that there are no more possible terms for a document. The more exhaustive the index is, the more terms it has
