A Constraint-based Representation Scheme of Collocational 
Structures 
Dirk Heylent Andr6 Schenkt Marc Verhagenl: 
(heylen@let.ruu.nl) (schenk@let.ruu,nl) (verhm@sx.ac.uk) 
t OTS - Trans 10 -3512 JK Utrecht (NL) 
CLMT Essex University - Wivenhoe Park - C04 3SQ Colchester (UK) 
1 Introduction 
The main aim of the ET-10/?5 project, 'Collocations 
and the Lexicalisation of Semantic Operations '1, is 
to evaluate the use of Mel'~uk's analysis of colloca- 
tions in terms of lexical functions 2, as an interlin- 
gun device in a machine translation system. In this 
poster we only point out the main design issues in- 
volved in encoding the essential parts of this analysis 
in an HPSG-style framework. Other aspects of the 
project, such as the definition of collocations, or the 
evaluation of the analysis as such, will not be dealt 
with. The linguistic analysis of collocations (as far 
as it is dealt with in this poster) involves two major 
issues. 
• Coding the Mel'~ukian analysis in an HPSG-Iike 
grammar. 
• Designing the architecture of the lexicon. 
2 Analysis 
Examples of the collocational structures we have in 
mind are strong criticism (as an adjective-noun com- 
bination) and give a demonstration (as a verb-noun 
combination). The essential characteristics we want 
to account for in our analysis are the following. 
• The collocational cooccurrence restriction. 
• The dependence of the meaning of the collocate 
on the combination. 
• The relation between the 'collocate occurrence' 
of a word and its free occurrence. 
Following Mel'Suk, the restricted choice of the par- 
ticular adjective or verb is represented in the dictio- 
nary by means of lexical functions. The dictionary 
entry for criticism contains a section in which its 'col- 
locates' are listed, indexed by a lexical function. In 
this case, we would find: Magn(criticism) = strong. 
This points out that you can use strong when you 
want to express Magn(criticism). In our interpre- 
tation of these lexical functions, we take them to be 
general semantic operations, representing the major 
semantic contribution of the collocate. So we say 
that strong means Magn (= very, intense ...) in the 
context of criticism. 
As far as translation is concerned, we no longer 
need a transfer rule mapping 'strong criticism' on 
Z We would hereby like to acknowledge the financial 
support by the Commission of the European Commu- 
nity, Association Suissetra (Geneva) and Oxford Univer- 
sity Press. 
2See for instance \[Mel'(~uk and ~olkovsky, 1988\]. 
'scherpe kritiek' (lit. sharp criticism)because if both 
are analyzed as the interlingual Magn, we can leave 
the correct choice of adjective to the monolingual 
components. 
The HPSG grammars we are using, closely resem- 
ble the proposals in \[Pollard and Sag, 1987\]. As far 
as the coding of the lexical functions is concerned, 
we have simply interpreted these as relation names. 
3 Representation 
Besides the use of a Mel'~ukian analysis and the 
choice of an HPSG-style grammar, one of the design 
criteria that has guided the representation is to be 
'minimally redundant'. This has led to the following 
solution. 
• The collocate is only specified by a partial lex- 
ical entry, which is a generalization of its 'free- 
occurring' counterpart (its meaning is left un- 
specified, for instance). 
• In the lexicon, it is specified on the base which 
collocates it selects for a particular lexical func- 
tion. The remainder of the collocation specific 
information about the collocate is specified here 
as well. 
The following is part of the entry for criticism to 
illustrate the latter issue. The COL field provides 
the information that to express Magn(criticism), it 
can combine with strong. The reference Sstrong is 
to the collocate entry in the dictionary. 
$criticism: PHONcritieisrn 
COL {,.trong\[ 
CONT,IND \[ VAR\[1\] 
References 
\[Heylen el al., 1993\] Dirk Heylen, Andr6 Schenk, 
and Marc Verhagen. A unification-based repre- 
sentation scheme of collocational structures, to 
appear, 1993. 
\[Mel'~uk and Zolkovsky, 1988\] I.A. Mel'~uk and 
A.K. 7,olkovsky. The explanatory combinatorial 
dictionary. In M. Evens, editor, Relational Mod- 
els in the Lexicon, pages 41-74. CUP, Cambridge, 
1988. 
\[Pollard and Sag, 1987\] Carl Pollard and Ivan Sag. 
Information Based Syntax and Semantics. CSLI, 
Stanford, 1987. 
469 
