Isolating Cross-linguistic Parsing Complexity with a Principles-and-Parameters Parser: A Case Study of Japanese and English

1 Introduction As parsing models and linguistic theories have broad ened to encorapass a wider range of non-English languages , a particularly uscfifl "stress test" is to buikl a single theory/parser pair that can work for multiple languages , in the best case with minor variation, perhaps restricted to the lexicon. This paper reports on the re-suits of just such a test applied to a fully operational (Prolog) implementation of a so-called principles-and-parameters model of syntax, for the case of Japanese and English. This paper has two basic aims: (1) to show how an implemented model tbr an entire principles-and-parameters model (essentially all of the linguistic theory in Lasnik & Uriagereka (1988)), see figure 2 for a computer snapshot, leads directly to both a parser for nml-tiple languages and a useful "computational linguistics workbench" in which one can easily experiment with alternative linguistic theoretical tormulations of gram-marital principles as well as alternative computational strategies; (2) to use this system to uncover sources of parsing complexity in Japanese as opposed to En-glish. In particular, we examine the "null hypothesis" that a single parsing design suffices for efficient processing of both/lead-first and Ilead-final languages, in contrast to approaches that posit, e.g., a right-corner or other mirror-image strategy for parsing Japanese as compared to English (e.g., BUP; Mazuka (1990)). In this case we can confirm computationally and precisely, in accordance with nmch current psychollnguisitic work (l'~razier and Raynert (1988); lnoue and J.1). Fodor (1991); Nagai (1991)) that it is not the lien&final character of Japanese that results in processing difficulty so mudl as the possibility of scrambling and free deletion of NPs (so-called "super Pro Drol)"). We do this by empirically investigating the effects of 3 t)ossi-ble "optimizations" of the parsing system for Japanese: (1) the use of right-context information via automatic source transformations, using a l,rogramming language compiler technique to introduce dummy nonterminals and corresponding semantic actions; (2) modification of the Japanese grammar to put the specitier of CP *Tiffs research ltas been supported by NSF (~raltt DCR85552543 under a Presidential Young fnvestiglttor Award to Professor Robert C. Berwiek, and a grant front the Kapor Family Foundation. We would like to thank linward Lasnik, Alec Marantz, Shigeru Miyagawa, David Pesetsky, and Mamoro Saito for valuable discussions and valiant attempts to tell us about Japanese. (= S) on tile right and so eliminate unnecessary center-embedding; and (3) eliminating of scrambling and NP drop …