Notes on computational linguistics.pdf - UCLA Department of ...
Notes on computational linguistics.pdf - UCLA Department of ...
Notes on computational linguistics.pdf - UCLA Department of ...
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Stabler - Lx 185/209 2003<br />
12.5 Binary relati<strong>on</strong>s am<strong>on</strong>g properties <strong>of</strong> things<br />
Now we turn to binary quantifiers. Most English quantifiers are binary. In fact, everything, every<strong>on</strong>e, something,<br />
some<strong>on</strong>e, nothing, no<strong>on</strong>e, are obviously complexes built from the binary quantifiers every, some, no and a noun<br />
thing, <strong>on</strong>e that specifies what “sort” <strong>of</strong> thing we are talking about. A binary quantifier is a binary relati<strong>on</strong><br />
am<strong>on</strong>g properties <strong>of</strong> things. Unfortunately, there are too many too diagram easily, because in a universe <strong>of</strong><br />
n things, there are 2n properties <strong>of</strong> things, and so 2n × 2n = 22n pairs <strong>of</strong> properties, and 222n sets <strong>of</strong> pairs <strong>of</strong><br />
properties <strong>of</strong> things. So in a universe <strong>of</strong> 2 things, there are 4 properties, 16 pairs <strong>of</strong> properties, and 65536 sets<br />
<strong>of</strong> pairs <strong>of</strong> properties. We can c<strong>on</strong>sider some examples though:<br />
[[every]] ={〈p, q〉| p ⊆ q}<br />
[[some]] ={〈p, q〉| (p ∩ q) = ∅}<br />
[[no]] ={〈p, q〉| (p ∩ q) =∅}<br />
[[exactly N]] ={〈p, q〉| |p ∩ q| =N} for any N ∈ N<br />
[[at least N]] ={〈p, q〉| |p ∩ q| ≥N} for any N ∈ N<br />
[[at most N]] ={〈p, q〉| |p ∩ q| ≤N} for any N ∈ N<br />
[[all but N]] ={〈p, q〉| |p − q| =N} for any N ∈ N<br />
[[between N and M]] ={〈p, q〉| N ≤|p ∩ q| ≤M} for any N,M ∈ N<br />
[[most]] ={〈p, q〉| |p − q| > |p ∩ b|}<br />
[[the N]] ={〈p, q〉| |p − q| =0and|p ∩ q| =N} for any N ∈ N<br />
For any binary quantifier Q we use ↑Q to indicate that Q is (m<strong>on</strong>ot<strong>on</strong>e) increasing in its first argument,<br />
which means that whenever 〈p, q〉 ∈Q and r ⊇ p then 〈r,q〉∈Q. Examplesaresome and at least N.<br />
For any binary quantifier Q we use Q↑ to indicate that QQis (m<strong>on</strong>ot<strong>on</strong>e) increasing in its sec<strong>on</strong>d argument<br />
iff whenever 〈p, q〉 ∈Q and r ⊇ q then 〈p, r〉 ∈Q. Examplesareevery, most, at least N, the, infinitely many,….<br />
For any binary quantifier Q we use ↓Q to indicate that Q is (m<strong>on</strong>ot<strong>on</strong>e) decreasing in its first argument,<br />
which means that whenever 〈p, q〉 ∈Q and r ⊆ p then 〈r,q〉∈Q. Examplesareevery, no, all, at most N,…<br />
For any binary quantifier Q we use Q↓ to indicate that QQis (m<strong>on</strong>ot<strong>on</strong>e) decreasing in its sec<strong>on</strong>d argument<br />
iff whenever 〈p, q〉 ∈Q and r ⊆ q then 〈p, r〉 ∈Q. Examplesareno, few, fewer than N, at most N,….<br />
Since every is decreasing in its first argument and increasing in its sec<strong>on</strong>d argument, we sometimes write<br />
↓every↑. Similarly, ↓no↓, and↑some↓.<br />
13 Correcti<strong>on</strong>: quantifiers as functi<strong>on</strong>als<br />
14 A first inference relati<strong>on</strong><br />
We will define our inferences over derivati<strong>on</strong>s, where these are represented by the lexical items in those derivati<strong>on</strong>s,<br />
in order. Recall that this means that a sentence like<br />
Every student sings<br />
is represented by lexical items like this (ignoring empty categories, tense, movements, for the moment):<br />
sings every student.<br />
If we parenthesize the pairs combined by merge, we have:<br />
(sings (every student)).<br />
The predicate <strong>of</strong> the sentence selects the subject DP, and the D inside the subject selects the noun. Thinking<br />
<strong>of</strong> the quantifier as a relati<strong>on</strong> between the properties [student] and [sing], we see that the predicate [sing] is,<br />
in effect, the sec<strong>on</strong>d argument <strong>of</strong> the quantifier.<br />
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