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

Stabler - Lx 185/209 2003
(142) We could have a stochastic grammar that recognizes some of these possible sentences too.
/*
* file: g6rdin.pl
*/
:- op(1200,xfx,:˜).
s :˜ [ip,terminator]/1. terminator :˜ [’.’]/1.
ip :˜ [dp, i1]/1. i1 :˜ [i0, vp]/1.0. i0 :˜ [will]/0.4.
i0 :˜ []/0.6.
dp :˜ [’I’]/0.1.
dp :˜ [dp,ap]/0.1.
dp :˜ [’Mary’]/0.1. dp :˜ [’John’]/0.1.
dp :˜ [d1]/0.6. d1 :˜ [d0, np]/1.0. d0 :˜ [the]/0.55.
d0 :˜ [a]/0.44.
d0 :˜ [some]/0.01.
np :˜ [n1]/1. n1 :˜ [n0]/1. n0 :˜ [saw]/0.2.
n0 :˜ [eye]/0.2.
n0 :˜ [air]/0.2.
n0 :˜ [mare]/0.2.
n0 :˜ [’E’]/0.2.
vp :˜ [v1]/1. v1 :˜ [v0,dp]/0.7. v0 :˜ [know]/0.3
v1 :˜ [v0,ip]/0.3. v0 :˜ [saw]/0.7.
ap :˜ [a1]/1.
startCategory(s).
a1 :˜ [a0]/1. a0 :˜ [summery].
a0 :˜ [airy].
a0 :˜ [merry].
What does the PCFG suggest as the value of
P(I-DP know-V John-DP saw-V Mary-DP|Grammar)?
How should these estimates of the two models be combined?
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