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Notes on computational linguistics.pdf - UCLA Department of ...

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Stabler - Lx 185/209 2003<br />

A, B for the predicates and Q for the determiner in sentences like every student laugh -s, QAB,whichgets<br />

a syntactic analysis <strong>of</strong> the form B(Q(A)) since Q selects A and then B selects Q. We capture many entailment<br />

relati<strong>on</strong>s am<strong>on</strong>g sentences <strong>of</strong> this form with schemes like the following, depending <strong>on</strong> the determiners Q. 53<br />

B(Q(A)) C(every(B))<br />

C(Q(A))<br />

[Q↑]<br />

(f or any r ight m<strong>on</strong>ot<strong>on</strong>e incr easing Q: all, most,<br />

the, at least N, inf initely many,...)<br />

B(Q(A)) B(every(C))<br />

C(Q(A))<br />

(f or any r ight m<strong>on</strong>ot<strong>on</strong>e decr easing Q: no, f ew,<br />

[Q↓]<br />

f ewer than N, at most N,...)<br />

B(Q(A)) C(every(A))<br />

B(Q(C))<br />

(f or any lef t m<strong>on</strong>ot<strong>on</strong>e increasing Q: some, at least N,<br />

[↑Q]<br />

...)<br />

B(Q(A)) A(every(C))<br />

B(Q(C))<br />

(f or any lef t m<strong>on</strong>ot<strong>on</strong>e decreasing Q: no, ever y, all,<br />

[↓Q]<br />

at most N, at most f initely many,...)<br />

There is an absolutely fundamental insight here: substituti<strong>on</strong> <strong>of</strong> a “greater” c<strong>on</strong>stituent is sound in a increasing<br />

c<strong>on</strong>text, and substituti<strong>on</strong> <strong>of</strong> a “lesser” c<strong>on</strong>stituent is sound in an decreasing c<strong>on</strong>text. It is worth spelling out<br />

this noti<strong>on</strong> <strong>of</strong> “c<strong>on</strong>text” more carefully.<br />

A competent language user learns more specific informati<strong>on</strong> about each verb too, some <strong>of</strong> which can be<br />

encoded in schemes roughly like this:<br />

v(praise(Obj),Subj)<br />

v(think,Subj)<br />

v(eat(Obj),Subj)<br />

v(eat,Subj)<br />

v(prefer(Obj),Subj)<br />

v(think,Subj)<br />

v(eat,Subj)<br />

v(eat(some(thing)),Subj)<br />

v(doubt(Obj),Subj)<br />

v(think,Subj)<br />

v(w<strong>on</strong>der(Obj),Subj)<br />

v(think,Subj)<br />

53Since ↑every↓, the “Barbara” syllogism is an instance <strong>of</strong> the rule [Q ↑]. Since ↓no↓, the “Celarent” syllogism is an instance <strong>of</strong> the<br />

rule [↓ Q].<br />

251

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