1. Trang chủ
  2. » Luận Văn - Báo Cáo

Báo cáo khoa học: "A GENERAL COMPUTATIONAL MODEL FOR WORD-FORM RECOGNITION AND PRODUCTION" potx

4 264 0
Tài liệu đã được kiểm tra trùng lặp

Đang tải... (xem toàn văn)

THÔNG TIN TÀI LIỆU

Thông tin cơ bản

Tiêu đề A General Computational Model For Word-Form Recognition And Production
Tác giả Kimmo Koskenniemi
Trường học University of Helsinki
Chuyên ngành General Linguistics
Thể loại báo cáo khoa học
Thành phố Helsinki
Định dạng
Số trang 4
Dung lượng 320,99 KB

Các công cụ chuyển đổi và chỉnh sửa cho tài liệu này

Nội dung

Trang 1

Kimmo K o s k e n n i e m i

D e p a r t m e n t of G e n e r a l L i n g u i s t i c s

U n i v e r i s t y of H e l s i n k i

H a l l i t u s k a t u 11-13, H e l s i n k i 10, F i n l a n d

A B S T R A C T

A l a n g u a g e i n d e p e n d e n t m o d e l f o r

r e c o g n i t i o n a n d p r o d u c t i o n of w o r d f o r m s

is p r e s e n t e d T h i s " t w o - l e v e l m o d e l " is

b a s e d on a n e w w a y of d e s c r i b i n g m o r p h o -

logical alternations All rules d e s c r i b i n g

the m o r p h o p h o n o l o g i c a l v a r i a t i o n s are par-

a l l e l and r e l a t i v e l y i n d e p e n d e n t of e a c h

other I n d i v i d u a l rules are i m p l e m e n t e d as

f i n i t e s t a t e a u t o m a t a , as in an e a r l i e r

m o d e l d u e to M a r t i n K a y a n d R o n K a p l a n

The t w o - l e v e l m o d e l has been i m p l e m e n t e d

as an o p e r a t i o n a l c o m p u t e r p r o g r a m s in

s e v e r a l p l a c e s A n u m b e r of o p e r a t i o n a l

t w o - l e v e l d e s c r i p t i o n s have been w r i t t e n

or are in p r o g r e s s ( F i n n i s h , E n g l i s h ,

J a p a n e s e , R u m a n i a n , F r e n c h , S w e d i s h , O l d

C h u r c h S l a v o n i c , G r e e k , L a p p i s h , A r a b i c ,

Icelandic) The model is b i d i r e c t i o n a l and

it is c a p a b l e of b o t h a n a l y z i n g and s y n -

thesizing word-forms

I G e n e r a t i v e p h o n o l o g y

The f o r m a l i s m of g e n e r a t i v e p h o n o l o g y

has b e e n w i d e l y u s e d s i n c e its i n t r o d u c -

t i o n in the 1960's T h e m o r p h o l o g y of a n y

language may be d e s c r i b e d w i t h the f o r m a l -

i s m by c o n s t r u c t i n g a set of r e w r i t i n g

rules The rules start from an u n d e r l y i n g

l e x i c a l r e p r e s e n t a t i o n , and t r a n s f o r m it

step by step until the surface r e p r e s e n t a -

tion is reached

The g e n e r a t i v e f o r m a l i s m is unidirec-

t i o n a l and it has p r o v e n to be c o m p u t a -

t i o n a l l y d i f f i c u l t , and t h e r e f o r e it has

found little use in p r a c t i c a l m o r p h o l o g i -

cal programs

2 T h e m o d e l of K a y a n d K a p l a n

M a r t i n Kay and Ron Kaplan from Xerox

P A R C n o t i c e d that e a c h of the g e n e r a t i v e

r e w r i t i n g r u l e s can be r e p r e s e n t e d by a

f i n i t e s t a t e a u t o m a t o n (or t r a n s d u c e r )

(Kay 1982) S u c h an a u t o m a t o n w o u l d c o m -

pare two successive levels of the genera-

tive f r a m e w o r k : the l e v e l i m m e d i a t e l y

T h e w o r k d e s c r i b e d in this p a p e r is a p a r t

of the p r o j e c t 593 sponsored by the A c a d e -

my of Finland

b e f o r e a p p l i c a t i o n of the rule, and the

l e v e l a f t e r a p p l i c a t i o n of the rule T h e

w h o l e m o r p h o l o g i c a l g r a m m a r w o u l d then be

a c a s c a d e of such levels and automata:

l e x i c a l

r e p r e s e n t a t i o n

IFSA II

t

after ist rule

t

after 2nd rule

!

t

after (n-1)st rule

surface

r e p r e s e n t a t i o n

A c a s c a d e of a u t o m a t a is n o t o p e r a -

t i o n a l as such, b u t K a y and K a p l a n n o t e d

t h a t the a u t o m a t a c o u l d be m e r g e d i n t o a

s i n g l e , l a r g e r a u t o m a t o n by u s i n g the

t e c h n i q u e s of a u t o m a t a t h e o r y T h e l a r g e

a u t o m a t o n w o u l d be f u n c t i o n a l l y identical

to the c a s c a d e , a l t h o u g h s i n g l e r u l e s could no more be identified w i t h i n it The

m e r g e d a u t o m a t o n w o u l d be both o p e r a t i o n -

al, e f f i c i e n t and b i d i r e c t i o n a l G i v e n a

l e x i c a l r e p r e s e n t a t i o n , it w o u l d p r o d u c e the surface form, and, vice versa, g i v e n a surface form it w o u l d guide lexical search and locate the a p p r o p r i a t e e n d i n g s in the lexicon

In p r i n c i p l e , t h e a p p r o a c h s e e m s ideal But there is one vital problem: the size of the m e r g e d automaton D e s c r i p t i o n s

of l a n g u a g e s w i t h c o m p l e x m o r p h o l o g y , such

as F i n n i s h , s e e m to r e s u l t in v e r y l a r g e

m e r g e d a u t o m a t a A l t h o u g h t h e r e are no

c o n c l u s i v e n u m e r i c a l e s t i m a t e s yet, it

s e e m s p r o b a b l e t h a t the s i z e m a y g r o w

p r o h i b i t i v e l y large

3 The t w o - l e v e l a p p r o a c h

M y a p p r o a c h is c o m p u t a t i o n a l l y close

to that of Kay and Kaplan, but it is based

on a d i f f e r e n t m o r p h o l o g i c a l t h e o r y In-

Trang 2

l i n e s of c o n c r e t e or n a t u r a l m o r p h o l o g y

(e.g L i n e l l , J a c k e n d o f f , Zager, D r e s s l e r ,

W u r z e l ) U s i n g t h i s a l t e r n a t i v e o r i e n t a -

t i o n I a r r i v e at a t h e o r y , w h e r e t h e r e is

no n e e d for m e r g i n g the a u t o m a t a in o r d e r

to r e a c h an o p e r a t i o n a l system

T h e t w o - l e v e l m o d e l r e j e c t s a b s t r a c t

l e x i c a l r e p r e s e n t a t i o n s , i.e t h e r e n e e d

n o t a l w a y s be a s i n g l e i n v a r i a n t u n d e r -

l y i n g r e p r e s e n t a t i o n S o m e v a r i a t i o n s are

c o n s i d e r e d s u p p l e t i o n - l i k e a n d a r e n o t

d e s c r i b e d w i t h rules T h e role of r u l e s is

r e s t r i c t e d to o n e - s e g m e n t v a r i a t i o n s ,

w h i c h a r e f a i r l y n a t u r a l A l t e r n a t i o n s

w h i c h a f f e c t m o r e t h a n o n e s e g m e n t , or

w h e r e t h e a l t e r n a t i n g s e g m e n t s a r e u n r e -

lated, are c o n s i d e r e d s u p p l e t i o n - l i k e and

h a n d l e d by the l e x i c o n system

4 T w o - l e v e l r u l e s

T h e r e are o n l y t w o r e p r e s e n t a t i o n s in

the t w o - l e v e l model: the l e x i c a l r e p r e s e n -

t a t i o n and the s u r f a c e r e p r e s e n t a t i o n N o

i n t e r m e d i a t e s t a g e s "exist", e v e n in p r i n -

c i p l e T o d e m o n s t r a t e t h i s , w e t a k e a n

e x a m p l e f r o m F i n n i s h m o r p h o l o g y T h e n o u n

l a s i 'glass' r e p r e s e n t s the p r o d u c t i v e and

m o s t c o m m o n t y p e of n o u n s e n d i n g in i T h e

l e x i c a l r e p r e s e n t a t i o n of t h e p a r t i t i v e

p l u r a l f o r m c o n s i s t s of the s t e m l a s i , the

p l u r a l m o r p h e m e I, and the p a r t i t i v e e n d -

ing A In the t w o - l e v e l f r a m e w o r k we w r i t e

t h e l e x i c a l r e p r e s e n t a t i o n l a s i I A a b o v e

the s u r f a c e f o r m laseja:

L e x i c a l

r e p r e s e n t a t i o n : 1 a s i I A

S u r f a c e

r e p r e s e n t a t i o n : 1 a s e j a

T h i s c o n f i g u r a t i o n e x h i b i t s t h r e e m o r p h o -

p h o n o l o g i c a l v a r i a t i o n s :

a) S t e m f i n a l i is r e a l i z e d as e in

f r o n t of t y p i c a l p l u r a l f o r m s , i.e w h e n I

f o l l o w s o n t h e l e x i c a l l e v e l , s c h e m a t i -

b) T h e p l u r a l I i t s e l f is r e a l i z e d a s j

if it o c c u r s b e t w e e n v o w e l s o n t h e s u r -

face, s c h e m a t i c a l l y :

V V

c) T h e p a r t i t i v e e n d i n g , l i k e o t h e r e n d -

ings, a g r e e s w i t h the s t e m w i t h r e s p e c t to

v o w e l h a r m o n y A n a r c h i p h o n e m e A is u s e d

i n s t e a d of t w o d i s t i n c t p a r t i t i v e endings

It is r e a l i z e d as ~ or a a c c o r d i n g to t h e

h a r m o n i c v a l u e of the stem, s c h e m a t i c a l l y :

s p e c i f y h o w l e x i c a l a n d s u r f a c e r e p r e s e n -

t a t i o n s m a y c o r r e s p o n d to e a c h other For

e a c h l e x i c a l s e g m e n t o n e m u s t d e f i n e t h e

v a r i o u s p o s s i b l e s u r f a c e r e a l i z a t i o n s T h e rule c o m p o n e n t s h o u l d s t a t e the n e c e s s a r y and s u f f i c i e n t c o n d i t i o n s for e a c h a l t e r - native A r u l e f o r m a l i s m has b e e n d e s i g n e d for e x p r e s s i n g s u c h s t a t e m e n t s

A t y p i c a l t w o - l e v e l rule s t a t e s that

a l e x i c a l s e g m e n t m a y be r e a l i z e d in a

c e r t a i n w a y if a n d o n l y i f a c o n t e x t c o n -

d i t i o n is m e t T h e a l t e r n a t i o n (i) in t h e

a b o v e e x a m p l e c a n be e x p r e s s e d as t h e

f o l l o w i n g t w o - l e v e l rule:

T h i s r u l e s t a t e s t h a t a l e x i c a l i m a y be

r e a l i z e d a s a n e o n l y i f it is f o l l o w e d b y

a p l u r a l I, a n d if w e h a v e a l e x i c a l i in

s u c h a n e n v i r o n m e n t , it m u s t be r e a l i z e d

a s e (and as n o t h i n g e l s e ) B o t h s t a t e -

m e n t s a r e needed: the f o r m e r to e x l u d e i-e

c o r r e s p o n d e n c e s o c c u r r i n g e l s e w h e r e , a n d

t h e l a t t e r to p r e v e n t t h e d e f a u l t i - i

c o r r e s p o n d e n c e in this context

R u l e (i') r e f e r r e d t o a l e x i c a l s e g -

m e n t I, a n d it d i d n o t m a t t e r w h a t w a s t h e

s u r f a c e c h a r a c t e r c o r r e s p o n d i n g to it ( t h u s t h e p a i r I - = ) T h e f o l l o w i n g r u l e

g o v e r n s the r e a l i z a t i o n of I:

< ° > v - - - v

T h i s rule r e q u i r e s t h a t the p l u r a l I m u s t

be b e t w e e n v o w e l s on the surface B e c a u s e

c e r t a i n s t e m f i n a l v o w e l s are r e a l i z e d as

z e r o in f r o n t of p l u r a l I, t h e g e n e r a t i v e

p h o n o l o g y o r d e r s t h e r u l e f o r p l u r a l I to

be a p p l i e d a f t e r the r u l e s for s t e m f i n a l

v o w e l s In t h e t w o - l e v e l f r a m e w o r k t h e r e

is n o s u c h o r d e r i n g T h e r u l e s o n l y s t a t e

a s t a t i c c o r r e s p o n d e n c e r e l a t i o n , and t h e y are n o n d i r e c t i o n a l and p a r a l l e l

5 R u l e s as a u t o m a t a

I n t h e f o l l o w i n g w e c o n s t r u c t a n

a u t o m a t o n w h i c h p e r f o r m s t h e c h e c k i n g

n e e d e d f o r t h e i - e a l t e r n a t i o n d i s c u s s e d

a b o v e I n s t e a d of s i n g l e c h a r a c t e r s , t h e

a u t o m a t o n a c c e p t s c h a r a c t e r p a i r s T h i s

a u t o m a t o n (and t h e a u t o m a t a f o r o t h e r rules) m u s t a c c e p t the f o l l o w i n g s e q u e n c e

of pairs:

i-I, a-a, s-s, i-e, I-j, A - a

T h e t a s k of the r u l e - a u t o m a t o n is to

p e r m i t t h e p a i r i - e if a n d o n l y if t h e

p l u r a l I f o l l o w s T h e f o l l o w i n g a u t o m a t o n

w i t h t h r e e s t a t e s (I, 2, 3) p e r f o r m s this:

Trang 3

(i")

S t a t e 1 is t h e i n i t i a l s t a t e of t h e a u t o m -

aton If t h e a u t o m a t o n r e c e i v e s p a i r s

w i t h o u t l e x i c a l i it w i l l r e m a i n in s t a t e

1 ( t h e s y m b o l = - = d e n o t e s " a n y o t h e r

pair") R e c e i v i n g a p a i r i - e c a u s e s a

t r a n s i t i o n to s t a t e 3 S t a t e s 1 a n d 2 a r e

f i n a l s t a t e s (denoted by d o u b l e circles),

i.e if the a u t o m a t o n is in one of t h e m at

t h e e n d of t h e i n p u t , t h e a u t o m a t o n a c -

c e p t s t h e i n p u t S t a t e 3 is, h o w e v e r , a

n o n f i n a l s t a t e , a n d t h e a u t o m a t o n s h o u l d

l e a v e it b e f o r e t h e i n p u t e n d s (or e l s e

t h e i n p u t is r e j e c t e d ) If t h e n e x t c h a r -

a c t e r p a i r h a s p l u r a l I a s i t s l e x i c a l

c h a r a c t e r ( w h i c h is d e n o t e d b Y I-=), t h e

a u t o m a t o n r e t u r n s to s t a t e 1 A n y o t h e r

p a i r w i l l c a u s e t h e i n p u t to be r e j e c t e d

b e c a u s e there is no a p p r o p r i a t e t r a n s i t i o n

arc T h i s p a r t of t h e a u t o m a t o n a c c o m -

p l i s h e s t h e " o n l y if" p a r t of t h e c o r r e -

s p o n d e n c e : the pair i-e is a l l o w e d o n l y if

it is f o l l o w e d by the p l u r a l I

T h e s t a t e 2 is n e e d e d f o r t h e "if"

part If a l e x i c a l i is f o l l o w e d by p l u r a l

I, w e m u s t h a v e t h e c o r r e s p o n d e n c e i-e

Thus, if we e n c o u n t e r a c o r r e s p o n d e n c e of

l e x i c a l i o t h e r than i-e (i-=) it m u s t not

be f o l l o w e d by the p l u r a l I A n y t h i n g e l s e

(=-=) w i l l r e t u r n t h e a u t o m a t o n to s t a t e

i

E a c h rule of a t w o - l e v e l d e s c r i p t i o n

m o d e l c o r r e s p o n d s to a f i n i t e s t a t e a u t o m -

a t o n as in the m o d e l of K a y and Kaplan In

t h e t w o - l e v e l m o d e l t h e r u l e s or t h e a u -

t o m a t a o p e r a t e , h o w e v e r , in p a r a l l e l i n -

s t e a d of b e i n g c a s c a d e d :

L e x i c a l

r e p r e s e n t a t i o n

T h e r u l e - a u t o m a t a c o m p a r e the t w o r e p r e -

s e n t a t i o n s , a n d a c o n f i g u r a t i o n m u s t be

a c c e p t e d b y e a c h of t h e m in o r d e r to be

valid

T h e t w o - l e v e l m o d e l (and the p r o g r a m )

o p e r a t e s in b o t h d i r e c t i o n s : t h e s a m e

d e s c r i p t i o n is u t i l i z e d as s u c h for p r o -

d u c i n g s u r f a c e w o r d - f o r m s f r o m l e x i c a l

r e p r e s e n t a t i o n s , and for a n a l y z i n g s u r f a c e

forms

As it s t a n d s now, t w o - l e v e l p r o g r a m s

r e a d t h e r u l e s as t a b u l a r a u t o m a t a , e.g

the a u t o m a t o n (i") is c o d e d as:

= e = =

T h i s e n t r y f o r m a t is, in f a c t , m o r e p r a c -

t i c a l t h a n the s t a t e t r a n s i t i o n d i a g r a m s

T h e t a b u l a r r e p r e s e n t a t i o n r e m a i n s m o r e

r e a d a b l e e v e n w h e n t h e r e are half a d o z e n

s t a t e s or m o r e It h a s a l s o p r o v e n to be

q u i t e f e a s i b l e e v e n for t h o s e w h o are lin-

g u i s t s r a t h e r t h a n c o m p u t e r p r o f e s s i o n a l s

A l t h o u g h it is f e a s i b l e t o w r i t e

m o r p h o l o g i c a l d e s c r i p t i o n s d i r e c t l y as

a u t o m a t a , this is far f r o m ideal T h e t w o -

l e v e l rule f o r m a l i s m is a m u c h m o r e r e a d -

a b l e w a y of d o c u m e n t i n g t w o - l e v e l d e s c r i p - tions, e v e n if h a n d c o m p i l e d a u t o m a t a are

u s e d in the a c t u a l i m p l e m e n t a t i o n A c o m -

p i l e r w h i c h w o u l d a c c e p t r u l e s d i r e c t l y in

s o m e t w o - l e v e l r u l e f o r m a l i s m w o u l d be of

g r e a t value T h e c o m p i l e r c o u l d a u t o m a t i -

c a l l y t r a n s f o r m t h e r u l e s i n t o f i n i t e

s t a t e a u t o m a t a , a n d t h u s f a c i l i t a t e t h e

c r e a t i o n of n e w d e s c r i p t i o n s a n d f u r t h e r

d e v e l o p m e n t of e x i s t i n g ones

5 T w o - l e v e l l e x i c o n s y s t e m

S i n g l e t w o - l e v e l r u l e s a r e at l e a s t

as p o w e r f u l as s i n g l e r u l e s of g e n e r a t i v e

p h o n o l o g y T h e t w o - l e v e l rule c o m p o n e n t as

a w h o l e (at l e a s t in p r a c t i c a l d e s c r i p -

t i o n s ) a p p e a r s to be l e s s p o w e r f u l , b e -

c a u s e of the lack of e x t r i n s i c rule o r d e r - ing

V a r i a t i o n s a f f e c t i n g l o n g e r s e q u e n c e s

of p h o n e m e s , or w h e r e the r e l a t i o n b e t w e e n the a l t e r n a t i v e s is p h o n o l o g i c a l l y o t h e r -

w i s e n o n n a t u r a l , a r e d e s c r i b e d b y g i v i n g

d i s t i n c t l e x i c a l r e p r e s e n t a t i o n s G e n e r a l -

i z a t i o n s are not l o s t s i n c e i n s o f a r as the

v a r i a t i o n p e r t a i n s to m a n y l e x e m e s , t h e

a l t e r n a t i v e s a r e g i v e n as a m i n i l e x i c o n

r e f e r r e d to by all e n t r i e s p o s s e s s i n g the

s a m e a l t e r n a t i o n

T h e a l t e r n a t i o n in w o r d s of the fol-

l o w i n g t y p e s are d e s c r i b e d u s i n g the m i n i -

l e x i c o n m e t h o d :

h e v o n e n - h e v o s e n 'horse'

v a p a u s - v a p a u t e n a

T h e l e x i c a l e n t r i e s of s u c h w o r d s g i v e s

o n l y t h e n o n v a r y i n g p a r t of t h e s t e m a n d

r e f e r s to a c o m m o n a l t e r n a t i o n p a t t e r n

n e n / S or s - t - k s / S :

h e v o n e n / S " H o r s e S";

v a p a u s - t - k s / S " F r e e d o m S";

T h e m i n i l e x i c o n s for the a l t e r n a t i o n p a t -

Trang 4

terns list the a l t e r n a t i v e lexical repre-

s e n t a t i o n s and a s s o c i a t e t h e m w i t h the

a p p r o p r i a t e sets of endings:

L E X I C O N nen/S

L E X I C O N s-t-ks/S

nen S 0 "" ;

sE S123 " "

s $0 "" ;

TE S13 "";

ksE $2 ""

6 C u r r e n t status

The t w o - l e v e l p r o g r a m has been imple-

m e n t e d f i r s t in P A S C A L l a n g u a g e and is

r u n n i n g at l e a s t on the B u r r o u g h s B 7 8 0 0 ,

DEC-20, and large IBM systems The p r o g r a m

is f u l l y o p e r a t i o n a l and r e a s o n a b l y f a s t

(about 0.05 C P U s e c o n d s per w o r d a l t h o u g h

h a r d l y a n y e f f o r t has b e e n s p e n t to o p t i -

m i z e the e x e c u t i o n speed) It c o u l d be

u s e d run on 128 kB m i c r o - c o m p u t e r e s as

well Lauri K a r t t u n e n and his students at

the U n i v e r s i t y of T e x a s h a v e i m p l e m e n t e d

the m o d e l in I N T E R L I S P ( K a r t t u n e n 1983,

G a j e k & al 1983, K h a n & al 1983) T h e

e x e c u t i o n s p e e d of t h e i r v e r s i o n is c o m -

parable to that of the PASCAL version The

t w o - l e v e l model has also been r e w r i t t e n in

Z e t a l i s p (Ken C h u r c h at Bell) and in N I L

(Hank B r o m l e y in Helsinki and Ume~)

The m o d e l has been tested by w r i t i n g

a c o m p r e h e n s i v e d e s c r i p t i o n of F i n n i s h

m o r p h o l o g y c o v e r i n g all t y p e s of n o m i n a l

and verbal inflection including c o m p o u n d -

ing (Koskenniemi, 1983a,b) K a r t t u n e n and

his students have m a d e t w o - l e v e l d e s c r i p -

t i o n s of J a p a n e s e , R u m a n i a n , E n g l i s h and

F r e n c h (see a r t i c l e s in T L F 22) At the

U n i v e r s i t y of Helsinki, two c o m p r e h e n s i v e

d e s c r i p t i o n s h a v e b e e n c o m p l e t e d : one of

S w e d i s h by O l l i B l ~ b e r g (1984) and one of

O l d C h u r c h S l a v o n i c by J o u k o L i n d s t e d t

(forthcoming) Further work is in p r o g r e s s

in H e l s i n k i for m a k i n g d e s c r i p t i o n s for

A r a b i c ( J a a k k o H ~ m e e n - A n t t i l a ) and for

M o d e r n Greek (Martti Nyman) The s y s t e m is

a l s o u s e d the U n i v e r s i t y of O u l u , w h e r e a

d e s c r i p t i o n for L a p p i s h is in p r o g r e s s

(Pekka S a m m a l l a h t i ) , in U p p s a l a , w h e r e a

more c o m p r e h e n s i v e F r e n c h d e s c r i p t i o n is

in p r o g r e s s (Anette Ostling), and in Goth-

enburg

The t w o - l e v e l m o d e l could be part of

a n y n a t u r a l l a n g u a g e p r o c e s s i n g s y s t e m

E s p e c i a l l y the a b i l i t y both to analyze and

to g e n e r a t e is u s e f u l S y s t e m s d e a l i n g

w i t h m a n y l a n g u a g e s , s u c h as m a c h i n e

t r a n s l a t i o n s y s t e m s , c o u l d b e n e f i t f r o m

the u n i f o r m l a n g u a g e - i n d e p e n d e n t f o r m a l -

ism The a c c u r a c y of i n f o r m a t i o n retrieval

s y s t e m s can be e n h a n c e d by using the two-

level m o d e l for d i s c a r d i n g hits w h i c h are

not t r u e i n f l e c t e d f o r m s of the s e a r c h

key T h e a l g o r i t h m c o u l d be a l s o u s e d for

d e t e c t i n g spelling errors

M y s i n c e r e t h a n k s are d u e to m y in- structor, p r o f e s s o r Fred Karlsson, and to

M a r t i n Kay, Ron Kaplan and Lauri K a r t t u n e n for fruitful ideas and for a c q u a i n t i n g me with their research

R E F E R E N C E S

Alam, Y., 1983 A T w o - L e v e l M o r p h o l o g i c a l

A n a l y s i s of Japanese In TLF 22

B l ~ b e r g , O., 1984 S v e n s k b ~ j n i n g s m o r f o -

l o g i : e n t i l l ~ m p n i n g a v t v ~ n i v ~ - modellen U n p u b l i s h e d seminar paper

D e p a r t m e n t of G e n e r a l L i n g u i s t i c s ,

U n i v e r s i t y of Helsinki

G a j e k , O., H B e c k , D E l d e r , and G W h i t - remote, 1983 KIMMO: LISP I m p l e m e n t a - tion In T L F 22

K a r l s s o n , F & K o s k e n n i e m i , K., f o r t h - coming A p r o c e s s m o d e l of m o r p h o l o g y and lexicon Folia Linguistica

K a r t t u n e n , L., 1983 K I M M O : A G e n e r a l

M o r p h o l o g i c a l Processor In TLF 22

K a r t t u n e n , L & R o o t , R & U s z k o r e i t , H.,

1981 TEXFIN: M o r p h o l o g i c a l analysis

of F i n n i s h by c o m p u t e r A p a p e r r e a d

at 7 1 s t M e e t i n g of the S A S S , A l b u - querque, N e w Mexico

K a r t t u n e n , L & W i t t e n b u r g , K., 1983 A

T w o - L e v e l M o r p h o l o g i c a l D e s c r i p t i o n

of E n g l i s h In T L F 22

Kay, M., 1982 W h e n m e t a - r u l e s are n o t

m e t a - r u l e s In S p a r c k - J o n e s & W i l k s (eds.) A u t o m a t i c n a t u r a l l a n g u a g e processing U n i v e r s i t y of Essex, Cog- nitive S t u d i e s Centre (CSM-10.) Khan, R., 1983 A T w o - L e v e l M o r p h o l o g i c a l

A n a l y s i s of Rumanian In TLF 22 Khan, R & Liu, J & Ito, T & S h u l d b e r g , K., 1983 K I M M O U s e r ' s M a n u a l In T L F

22

K o s k e n n i e m i , K., 1983a T w o - l e v e l M o d e l for M o r p h o l o g i c a l Analysis P r o c e e d - ings of IJCAI-83, pp 683-685

-, 1983b T w o - l e v e l M o r p h o l o g y : A Gen-

e r a l C o m p u t a t i o n a l M o d e l for W o r d -

F o r m R e c o g n i t i o n and Production Uni-

v e r s i t y of Helsinki, Dept of G e n e r a l

L i n g u i s t i c s , P u b l i c a t i o n s , No ii

L i n d s t e d t , J., f o r t h c o m i n g A t w o - l e v e l

d e s c r i p t i o n of O l d C h u r c h S l a v o n i c morphology Scando-Slavica

Lun, S., 1983 A T w o - L e v e l A n a l y s i s of

F r e n c h In T L F 22

TLF: T e x a s L i n g u i s t i c F o r u m D e p a r t m e n t

of L i n g u i s t i c s , U n i v e r s i t y of Texas, Austin, TX 78712

Ngày đăng: 31/03/2014, 17:20

TÀI LIỆU CÙNG NGƯỜI DÙNG

TÀI LIỆU LIÊN QUAN

🧩 Sản phẩm bạn có thể quan tâm