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From: vannoord@let.rug.nl (Gertjan van Noord)
Subject: Re: Context Sensitivity
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Message-ID: <1995Jan31.211106.28055@let.rug.nl>
Date: Tue, 31 Jan 1995 21:11:06 GMT
References: <447@mango.ukc.ac.uk> <D3ADuu.D2D@news.cis.umn.edu>
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In article <D3ADuu.D2D@news.cis.umn.edu> dogru@atto.cs.umn.edu (Sait Dogru) writes:
>In article <447@mango.ukc.ac.uk> A.M.L.Fowler@ukc.ac.uk (amlf) writes:
>>

< confusing remarks on context-sensitivity deleted >

let's make a distinction between a particular formalism called
`context-sensitive rewrite grammar' on the one hand and the
label `context-sensitive' on the other hand. In the first meaning,
grammar rules are allowed in which the number of symbols on the 
left-hand-side is not larger than the number of symbols on the right
hand side. This formalism is hardly used for NLP.

In the second meaning, context-sensitivity can be attributed to all
grammtical systems that have properly more power than context-free
systems. Such systems ARE used in NLP (TAGs, DCGs, PATR, .....).



