Book Reviews: Prosody and Speech Recognition

chart parsing is reduced into a set of matrix operations dealing with sparse matrices. Appendices list sample grammars and lexicons, which brings substance to the claims. "Speech" in this book refers to English only, which is never made explicit. This seems to be the normal case in American literature, however. Of course, most of the contribution is relevant to other languages as well. The book also provides an interesting contribution in the area of finite-state properties of language, because the phrase structure grammars used are essentially finite-state. Other finite-state accounts (such as the two-level model by Koskenniemi [1984] and cascaded transducers by Kaplan and Kay [Kay 1983] seem to have been less successful in combining structural information with segmental processes. Both other models are purely segmental, although syllables are sometimes referred to as contexts. An interesting problem concerning rule interaction in the proposed formalism is dealt with on page 113. There would be an obvious need for subtraction (for defining negative contexts) and intersection (combining effects). Subtraction, however, turns out to exclude too much, whereas intersection is too permissive. The book is well written and the argumentation proceeds logically. Both strong and weak points of the theories proposed are clearly presented. It gives a fair overall picture of the field of speech recognition, and much of the book could be suitable as a textbook. Nevertheless, some passages address mostly readers with a considerable background. The main topic covers, of course, a specific slice of the whole field, namely the treatment of allophonic variation. One minor inconvenience is the use of a reference format that cites a number only, not the author and the year. This results in a small savings in space but a larger burden for the reader. The book appears to be Church's (previously unpublished) doctoral dissertation from MIT, though this is not clearly indicated in the volume. Although not particularly new, it still is very valuable.