Recently, it was shown (KUHLMANN, SATTA: Tree-adjoining grammars are not closed under strong lexicalization .

Thus, simple context-free tree grammars strongly lexicalize tree adjoining grammars and themselves.

A good overview on TAG, their formal properties, their linguistic motivation, and their applications is presented by Joshi and Schabes (1992) and Joshi and Schabes (1997), in which also strong lexicalization is discussed.

In general, lexicalization is the process of transforming a grammar into an equivalent one (potentially expressed in another formalism) such that each production contains a lexical item (or anchor).

alphabet, each production of a lexicalized grammar produces at least one letter of the generated string.

Second, by replacing the syntactic features with an approximation based on POS tags, we achieve state-of-the-art performance without relying on error-prone unlexicalized or domain-specific lexicalized parsers.

Table 2 shows the three variations we tested: the simple tGR type, with parameterization for the POS tags of head and dependent, and with closed-class POS tags (determiners, pronouns and prepositions) lexicalized .

An unlexicalized parser cannot distinguish these based just on POS tags, while a lexicalized parser requires a large treebank.

As with tGRs, the closed-class tags can be lexicalized , but there are no corresponding feature sets for param (since they are already built from POS tags) or lim (since there is no similar rule-based approach).

The BioLexicon system extracts each verb instance’s GRs using the lexicalized Enju parser tuned to the biomedical domain (Miyao, 2005).

The BioLexicon system induces its SCF inventory automatically, but requires a lexicalized parsing model, rendering it more sensitive to domain variation.

Third, lexicalizing the closed-class POS tags introduces semantic information outside the scope of the alternation-based definition of subcategorization.

Nevertheless, as it does not have a lexicalized strategy, it is not able to filter out incorrect candidates; the precision is therefore very low (the worst).

They are often divided into two main classes: multiword expressions defined through linguistic idiomaticity criteria ( lexicalized phrases in the terminology of Sag et al.

They used a Tree Substitution Grammar instead of a Probabilistic Context-free Grammar (PCFG) with latent annotations in order to capture leXicalized rules as well as general rules.

We define and automatically extract a lexicalized approximation of the latter.

(ii) The second type of tree uses lexicals as central nodes on which both GR and POS-Tag are added as the rightmost children.

For LEX type, we apply a lexical similarity learned with LSA to only pairs of lexicals associated with the same POS-Tag.

Implicit) or overt, lexicalized as discourse connectives (i.e.

o AltLex: when insertion of a connective leads to redundancy due to the presence of an alternatively lexicalized expression, as in (2).

o NoRel: when neither a lexicalized discourse relation nor entity-based coherence is present.