Shows how to characterize language learning in a finite parameter space, such as in the "principles-and-parameters" approach, as a Markov structure. Explains how sample complexity varies with input distributions and learning regimes. Finds that a simple random-step algorithm always converges to the right target language and works faster than a…

Describes the indexing concept of entry terms, and evaluates existing terms in the Medical Subject Headings by comparing them to the results of an automatic indexer. The results of experimental testing of a strategy for creating entry terms using the algorithms of the automatic indexer are presented. (31 references) (CLB)

Presents an algorithm for use in natural language document retrieval systems which automatically determines if the conjunction "and" in a statement representing an information need should be translated into a Boolean "and" or "or." The results of an experiment that used the algorithm are reported, and further research is suggested. (CLB)