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

Stabler - Lx 185/209 2003
lex(’the’,[’D’,’@’]).
lex(’cat’,[’k’,’&’,’t’]).
lex(’cat-nap’,[’k’,’&’,’t’,’y’,’n’,’&’,’p’]).
lex(’is’,[’I’,’z’]).
lex(’island’,[’aI’,’l’,’@’,’n’,’d’]).
lex(’on’,[’0’,’n’]).
lex(’mat’,[’m’,’&’,’t’]).
lex(’matt’,[’m’,’&’,’t’]).
lex(’Matt’,[’m’,’&’,’t’]).
We can represent this dictionary with the following prefix transducer that maps phones to spelling as
follows:
lex
D:th
k:c
I:i
m:[]
[D]
[k]
[I]
[m]
@:e
&:a
z:s
a:[]
As discussed in class, in order to represent a finite state transducer, which is, in effect, a grammar with “output,”
we will label all the categories of the morphological component with terms of the form:
[D@]
[k&]
[Iz]
[m&]
category(output)
t:t
t:matt
t:Matt
t:mat
So then the machine drawn above corresponds to the following grammar:
[k&t]
[m&t]
lex([t,h|Rest]) :˜ [’D’,’[D]’(Rest)].
lex([c|Rest]) :˜ [k,’[k]’(Rest)].
lex([i|Rest]) :˜ [’I’,’[I]’(Rest)].
lex([o|Rest]) :˜ [’0’,’[0]’(Rest)]. % in Mitton notation, that’s a zero
lex(Rest) :˜ [m,’[m]’(Rest)].
’[D]’([’e’|Rest]) :˜ [’@’,’[D@]’(Rest)].
’[D@]’([]) :˜ [].
’[k]’([a|Rest]) :˜ [’&’,’[k&]’(Rest)].
’[k&]’([t|Rest]) :˜ [t,’[k&t]’(Rest)].
’[k&t]’([]) :˜ [].
’[I]’([s|Rest]) :˜ [z,’[Iz]’(Rest)].
’[Iz]’([]) :˜ [].
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