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

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Stabler - Lx 185/209 2003<br />

And if you are looking at this in color, we have used the colors green and blue to indicate the 6 quantifiers<br />

Q that are decreasing in the sense that if p ∈ Q and r ⊆ q then r ∈ Q. That is, they are closed under the<br />

subset relati<strong>on</strong>:<br />

{} {{}} {{j}, {}} {{m}, {}} {{j}, {m}, {}} {{j,m}, {j}, {m}, {}}.<br />

(If you d<strong>on</strong>’t have color, you should mark these yourself, to see where they are.) Notice that nothing denotes a<br />

decreasing quantifier.<br />

The color blue indicates the 2 quantifiers that are both increasing and decreasing, namely the top and<br />

bottom:<br />

{} {{j,m}, {j}, {m}, {}}.<br />

The first <strong>of</strong> these could be denoted by the expressi<strong>on</strong> something and nothing, and the sec<strong>on</strong>d by the expressi<strong>on</strong><br />

something or nothing.<br />

12.4 Binary relati<strong>on</strong>s am<strong>on</strong>g things<br />

The denotati<strong>on</strong>s <strong>of</strong> binary predicates will be relati<strong>on</strong>s am<strong>on</strong>g things, which we will identify “extensi<strong>on</strong>ally,”<br />

as the sets <strong>of</strong> pairs <strong>of</strong> things. When E is the set above, there are 16 different binary relati<strong>on</strong>s, namely,<br />

{,,,}<br />

{,,} {,,} {,,} {,,}<br />

{,} {,} {,} {,} {,} {,}<br />

{} {} {} {}<br />

So if <strong>on</strong>ly John loves Mary and Mary loves John, and no other love is happening, we will interpret loves as the<br />

property {〈j,m〉, 〈m, j〉},<br />

[[loves]] ={〈j,m〉, 〈m, j〉}.<br />

And the property <strong>of</strong> “being the very same thing as”<br />

{}<br />

[[is]] ={〈j,j〉, 〈m, m〉}.<br />

It is a good exercise to think about how each <strong>of</strong> these properties could be named, e.g.<br />

[[loves and doesn ′ tlove]] ={},<br />

[[loves or doesn ′ tlove]] ={〈j,j〉, 〈j,m〉, 〈m, j〉, 〈m, m〉}.<br />

Notice that some <strong>of</strong> the binary predicates are increasing, some are decreasing, and some are neither.<br />

236

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