Each of the four research papers in this book takes a novel formal approach to a particular problem in language acquisition. In the first paper, J. M. Siskind looks at developmentally inspired models of word learning. In the second, M. R. Brent and T. A. Cartwright look at how children could discover the sounds of words, given that word boundaries are not marked by any acoustic analog of the spaces between written words. In the third, P. Resnik measures the association between verbs and the semantic categories of their arguments that children likely use as clues to verb meanings. Finally, P. Niyogi and R. C. Berwick address the setting of syntactic parameters such as headedness--for example, whether the direct object comes before or after the verb.