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Re: the RM saga

==KEN: I'm not sure I get the last point.  Terry, are you suggesting
==KEN: that we do away with subtleties like 'conj_pp', etc.?  I'd be
==KEN: loath (or is that 'loathed'? ;-) to do it.  As an example, I
==KEN: call 'You can print on the laser printer OR on the plotter' as
==KEN: my first witness.  The disjunction would be lost.

No, just that in the 'the printer by ...' case, the PPs are on analysis 
not conj-ed in the and/or manner you illustrate.  Fact is, reattachment 
here is pushing the envelope of DIPETT's grammar--the user wants to create 
a (correct) structure that DIPETT will not produce on its own, always 
preferring to conj its PPs.  What to do? I ask.

***SYL: wait a second! Correctness is defined by DIPETT's grammar. It might
***SYL: be the case that for a specific string, DIPETT won't manage to
***SYL: find the right structure. However, it must be the case that whatever
***SYL: structure will be output by the RM, it must be a legal DIPETT parse
***SYL: tree that could have been produced by the parser if it had managed
***SYL: to parse "perfectly".

What structure is to be produced from reattachment of the conjoined PP 
phrases 'on the printer by the desk in the office'?  That's what I'm 
trying to find out.

DIPETT returns the single PP in "I printed the file on the printer" thus:

	svoo_svoc_svoa([ entity( ... ), pp( ... ) ]) 

and parses "I printed the file on the printer by the desk in the office" as:

	svoo_svoc_svoa([ entity( ... ),
		         conj_pps( implicit_and,
				   [ pp( ... ),
				     p_asyndetic_conj_pp( pp( ... ) ),
				     p_asyndetic_conj_pp( pp( ... ) )] ) ])
	
These are the raw materials.

We are agreed that a correct tree for the second sentence would have its
second and third PPs modifying the first, either hierarchically or in 
a flat list (Ken's question).

To remain entirely faithful to DIPETT, reattachment would modify the second
tree to resemble the first.  The first PP, 'on the printer', would remain
on the entity level and the other two PPs would be tucked into its object's
(=entity's) np_postmodifiers slot (as Ken discerned).  The conj_pps( 
implicit_and, ... ) frame would be stripped away from this first PP and 
shifted down as well, and the the p_asyndetic_conj_pp wrapper removed from 
the second PP after down-shifting.  A check that this was not the only PP 
would be needed; if so, the conj_pps frame would be dropped.  Lotsa overhead.

***SYL: let's not get into the quicksands of specific examples! The user
***SYL: will decide if this or that PP should be attached to the verb or
***SYL: the noun -- it's his business! The RM's business is to provide
***SYL: the reattachment fonctionality. 
But we might not provide the functionality of allowing PPs to modify 
other PPs, and instead insist that all PPs modifying a noun remain 
one level below the noun.  It is a theoretically defensible posture.

***SYL: ... And the latter must be able to
***SYL: deal with DIPETT parse trees on input and produce a legal DIPETT
***SYL: parse tree on output.
I thought we were in agreement on the sentence/4, clause/4, phrase/4
representation?  While these are intended to be reversible back into
a single parse tree, everyone seems to feel that a single tree structure
is too multifarious to be worked with.  As we leave syntax behind, why
not let the grammar evolve in the direction of simplicity and efficiency?
   
Sylvain (Aren't we going overboard with the current exchange!?)

Without any intention of being disagreeable, I thought Ken's observation 
was quite acute, and it does affect us here in terms of what functions
we decide to implement.  How NPs modify other NPs may be more important 
to Ken than to others given his dissertation topic. 

-- 
Terry Copeck (terry@csi.uottawa.ca)
References: