Technical Reports (CIS)

Document Type

Technical Report

Date of this Version

September 1988


University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-88-70.
This paper is a revised paper orginally presented at the First CUNY Workshop on Sentence Processing, CUNY, New York, February 1988.


The clause-final verbal clusters in Dutch and German (and in general, in West Germanic languages) has been extensively studied in different syntactic theories. Standard Dutch prefers crossed dependencies (between verbs and their arguments) while Standard German prefers nested dependencies. Recently Bach, Brown, and Marslen-Wilson (1986) have investigated the consequences of these differences between Dutch and German for the processing complexity of sentences, containing either crossed or nested dependencies. Stated very simply, their results show that Dutch is 'easier' than German, thus showing that the push-down automaton (PDA) cannot be the universal basis for the human parsing mechanism. They provide an explanation for the inadequacy of PDA in terms of the kinds of partial interpretations the dependencies allow the listener to construct. Motivated by their results and their discussion of these results we introduce a principle of partial interpretation (PPI) and present an automaton, embedded push-down automaton (EPDA) which permits processing of crossed and nested dependencies consistent with PPI. We show that there are appropriate complexity measures (motivated by the discussion in Bach, Brown, and Marslen-Wilson (1986) according to which the processing of crossed dependencies is easier than the processing of nested dependencies. This EPDA characterization of the processing of crossed and nested dependencies is significant because EPDAs are known to be exactly equivalent to Tree Adjoining Grammars (TAG), which are also capable of providing a linguistically motivated analysis for the crossed dependencies of Dutch (Kroch and Santorini 1988). This significance is further enhanced by the fact that two other grammatical formalisms, (Head Grammars (Pollard, 1984) and Combinatory Grammars (Steedman, 1987), also capable of providing analysis for crossed dependencies of Dutch, have been recently shown to be equivalent to TAGS in their generative power. We have also briefly discussed some issues concerning the degree to which grammars directly encode the processing by automata, in accordance with PPI.



Date Posted: 16 November 2007