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disambiguation tasks, collocational & phrasal patterning, & 'time'






Back from a long trip, now I can finally respond to the discussion 
on word sense.  



In what follows, I talk about Longman's entry for 'time' that Ted 
Dunning sent out. I first mention a couple issues relevant to the 
sense disambiguation task and then I query folks about a tiered 
approach for specifying word senses.

I.   On dictionary sense disambiguation tasks.

While Robert Amsler commented that he expects "true ambiguity 
resolution to find the distinctions between senses as detailed in a 
specific published dictionary," Ted Dunning noted that "people 
can't perform this disambiguation task with any reliability or 
even repeatability. " Dunning then queried whether this doesn't 
"seriously bring into [question] whether the task is pertinent to 
language processing?"

Actually, it strikes me as unsurprising that people don't replicate 
sense distinctions found in published dictionaries.

First,  Dictionaries vary rather wildly on the number of senses 
they attribute to a particular word.  For example, for the noun 
'time', Longman cites 50; Webster's III unabridged, 15 + 7 
expressions involving 'time'; Random House II unabridged, 26 + 
32 expressions; and Collins Cobuild English Language 
Dictionary cites 28 senses  + 11 expressions.

If dictionaries don't agree on the number (and therefore identity) 
of senses, why should any respondent replicate the distinctions of 
any particular published dictionary as opposed to any other? 
Never mind the dictionaries which have not yet been published.

Further, taking Longman's as an example, this dictionary relies   
q u i t e  heavily on collocational patterning in its statement of 
meaning.   Dictionary entries relying almost exclusively on 
collocational patterning can result in  definitions which are 
overly restricted which miss linguistic generalizations. 

While collocational patterning is obviously important, it's not the 
only patterning relevant to word meaning.  And actually, 
attention to the phrasal structure of collocations can point the 
way to syntactic generalizations that may prove useful in 
organizing a dictionary entry.

Here are two examples from Longman's entry for 'time'.

___________________
Sense 0100 reads as follows:
0100  	A continuous measurable quantity from the past through 
the present and into the future. 
ex.  (The universe exists in space and time)

Comment:  The gloss of quantity/extent (from past through 
present into the future) corresponds to what we know about 
universes,  not to the meaning of  'time' itself. 

Thus, in "A lighting bolt exists in time and space", we find no 
notion of continuous, measurable quantity, or of 
past/present/future.  

Longman  is building into the definition of 'time' information 
more properly associated with the definition of 'universe'.

Syntax provides a helpful toehold here.  [in .... time] is a 
prepositional phrase, exhibiting one of the typical prepositional 
phrase meanings -- location.  You can tell that because the wh-
interrogative query on the PP in example 0100 is "WHERE does 
the universe exist?"  not "when does the universe exist?".  The 
phrase structure of this reading is instrumental in pointing to 
basic aspects of its meaning.

______________________
Here's another example of how general syntactic information and 
collocational information interact in the statement of word 
meaning.

 Longman Definition: 1400 'the time':  the right occasion:  
ex.  (He's in a good temper, so now's the time to tell him you've 
made a serious mistake )

Comment:  It is certainly true, "the time" in 1400 receives the  
gloss of "the right occasion". However, there is more to the story.  
This reading is systematically related to others, specifically 
NP=[determiner  (X) time] where X is an adjective specifying a 
characteristic of time: ex. "Now's the right /wrong /perfect /worst 
time."  When the adjective is omitted, we get a default 
assumption of the "right" time. 

If the definition specified the general syntactic pattern 
NP=[det adj N], much of the meaning would be readily derivable 
and it would also key into the similar paradigmatic pattern:  [the

right/wrong/perfect/worst moment].


2.  A question  regarding a multi-tiered approach  to sense.

As I worked through the 50 senses of 'time' in Longman's, I 
realized that 'time' occurrs in 3 basic syntactic patterns:
	
	A) Prepositional phrases as head of a preposition, 
	B) Noun Phrases, as head, and
	C) Verb Phrases as object to a content verb

In each case,  looks to me like a good deal of the meanings stated 
in Longman's for 'time' stem from the preposition, or nominal 
modifiers, or content verb phrasally associated with 'time'. 

For example, 4000 [make good time],  Longman glosses as "to 
go that a speed that is satisfactory or better than expected".  But 
this example instantiates the more general pattern, VP=[make X 
time] (make good/poor/terrible/alright, etc. time.). So the 
meaning ought to read "go at a speed that is X relative to 
expectations].

Here are the 3 patterns, and Longman entries corresponding to 
them:

A)  PP [prep  time] 
encoding the usual types of PP meaning:
	(i)    location (stative, point, goal), 	
	(ii)   time (point, duration, iteration)
	(iii)  manner
Longman senses: 0100, 0500, 0700, 1700,  2000, 2100, 2200, 
2400, 2500, 2600, 2800, 2900, 3000, 3300, 3400, 3500, 3600, 
4200

B)  NP [(det) (adj) time]
	 modifiers (a, the, all, many, only, full, good, long, 	right 
	etc. ),  compounding (bedtime, summertime), near
	compounding (closing time).
Longman senses: 0300, 0400, 0600, 0800, 1200, 1300, 1400, 
1500, 1600, 1700, 1800, 1900, 2300, 4100, 4800, 4900

C)  VP [V time] 
	V= have, keep, (kill, pass, bide), do/serve, take, 
	make, play for
Longman senses:  1000, 1100, 2700, 3100, 3200, 3800, 3900, 
4000, 4500, 4600, 4700, 

Then there were some entries that seemed rather idiomatic or 
metaphoric to me... (3700  It's only a question/matter of time; 
4300 once upon a time; 5000 the time of one's life; 
0900 the rate of pay received for an hour's work) 

Here's my question:  

Would it be useful in NLP to

(i) make the first cut at the level of phrasal syntax (NP, PP, VP),  
drawing from word's syntactic position basic, typical  NP, PP, 
VP types of meaning, and 

(ii) then move on for more detail to the to collocational aspects of 
meaning in the word's immediate context?  

As is, in Longman's,  it seems that the lexicographers went 
straight to (ii), skipping all the semantic basic info. they could 
have drawn out of the basic phrasal patterning of (i).


rebecca wheeler
lexical semanticist