HPSG and GPSG

[Howard Anthony Gregory]

> But the PS-94 analysis of UDCs is GKPS-compatible, isn't it, assuming one
adds
> set-valued features to GPSG (as proposed by Maling and Zaenen 1983)?  And in
> this case, the SLASH-introduction analysis would involve neither a metarule
> nor a lexical rule, but it would allow multiple gaps.
> >>
>
> Yes, but then you lose context-freeness, since the set of categories
> becomes infinite. I think it was conjectured that you end up with the
> indexed languages, but I don't know if that was ever proved or disproved.

I would be interested if anybody knows any references on this question. I had
gathered from somewhere (and since assumed) that the HPSG framework has the
power of indexed grammars, though actual HPSG grammars (seek to) avoid this
infinite set of categories by restrictions on subcategorization etc.  But if
this is not definitely the case then I would be grateful for  more precise
information.

Many thanks,
Howard Gregory


___________________________

H. A. O. Gregory
Seminar für Englische Philologie
Georg-August-Universität Göttingen
Käte-Hamburger-Weg 3
37073 Göttingen
Deutschland

E-mail: howard.gregory at phil.uni-goettingen.de
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