A Case History in Computer Exploration of Fast Speech Rules

~d

of

Computational

Linguistics

A

C A S E

H I S T O R Y

G D M P U T E R

E X P L O R A T I O N

F A S T

S P E E C H R U L E S

Douglas

B.

M o r a n

"S;.

of

C o m p u t e r

&

Communication

Sciences

University

of

Michigan

Ann

A r b o r ,

Mlchigan

C o p y r i g h t

1 9 7 5

A b s t r a c t

-

-In c o n v e r s a t i o n a l

s p e e c h ,

words

r u n

t o q 6 t

her

a n d

i n t e r a c t

c a u s i n g

t h e i

p h o n o l o g i c a l

f ~ r m s

t o d i f f e r

from

t h e i r

c i t a t i o n

forms.

F a s t s p e e c h

r u l e s

a t t e m p t t3 q e s c r i b e

t h e s e

c h a n g e s

as

s p e e c h

becomes

f a s t e r

a n d

more

c a s u a l ,

In

d e v e l o p i n g

3

n y

s e t

of

p h o n o l o g i c a l

rules,

c o m p u t e r i z e d

grammar

t e s t e r s

a r e

a

u s e f u l

and

i m p o r t a n t

a i d . T h e y

n e c e s s i t a t e

(3.

p r e c i s e ,

a o n s i s t e n t E o r n u l a t i o n

of the

r u l e s a n d

allow

t h e

g e n e r a t i o n

of

s - p l e

d . e r i v a t i o n s .

I n

a p p l y i n g

these

~ u l e s

to

a

d i v e r s e

set

of utterances,

w e can

f i r s t

confirm

t h a t

t h e

r u l e s

r e a l l y

d c

a p p l y

where

we

e x p e c t

them to,

a n d

t h e n

experiment

v i t h

v a r i o u s

r u l e

o r d e r i n g s to o b s e r ~ e t h e i r e f f e c t s .

T h e

P h o n o l o g i c a l

G r a m m a r

Tester

of F r i e d m a n

a n d

Morin

was

use-d

t o t e s t

t w o s e t s Of*

f a s t

s p e ' e c h

rules from

t h e

A R Q A S p s e c h

U n d e r s t a n d i n g

R e s e a r c h

c c m m u n i t y .

Working

w i t h

C

hese

rules

l a d

t o

c e r t a i n o b s e r v a t i o n s

a b o u t t h e

i n t e r a c t i o n s and

n a t u r e

of

f a s t

s p e e c h

r u l e s

in

g e n e r a l .

3x1 a d d i t i o n

t o

t e s t i n g

t h e s e

t w o

sets

of

f a s t s p e e c h

r u l e s ,

we

were also

i n t e r e s t e d

in

t h e

p r o b l e m s

o f

t e S t i n g

such

a

grammar

v i t h

t h i s

program.

A p p e h d i c e s i n c l t l d e

an

overview

of

t h e

grammar

tester

a n d

Table

of

C o n t e n t s

---.lC

...

T e s t i n g

t h e

F a s t

S p e e c h

R u l e s

...

5

...

Sutgqested Wodif

i e a t i o n s

to

t ' h e

P G T

10

Observations

a b o u t

Fast

S p e e c h

Rules

...

1 2

References

...

1 5

A p p e n d i x A

.

Using

the

P h o n o l o g i c a l

Grammar

Tester

...m...m...

18

.

A p p e n d i x B S a m p l e O u t p u t

.m...

2 1

.

A p p e n d i x

C F i r s t

Set of

R u l e s

...

2 4

...

4

fi Case

History

i n

Computer E x p l o r a t i o n

o f

F a s t S p e e c h

R u l e s

C o u g l a s

B.

Moran

The

U n i v e r s i t y

of

M i c h i g a n

I n t r o d u c t i o n

- - - I - - - - * -

In

d e v e l o p i n g

a n y

sebt

o f

p h o n o l o g i c a l

r u l e s , computerized

grammar

t e s t e r s

are

a

useful

a n d

i m p o r t a n t

a i d .

T h e y

n e c e s s i t a t e

a

precise,

consistent

formulation

of

t h e

r u l e s

a n d

aL1ow t h e

g e n e r a t i c n

of

sample

d e r i v a t i o n s .

I n a p p l y i n g

t h ~ s e

r u l e s

to

a

d i v e r s e

set

of

utterances,

we can

f i r s t

confirm

t h a t

t h e

rules

r e a l l y

d o

3 p p l y

where

ue expect

t h e m

to,

a n d

t h e n

experiment

w i t h

v a r i o u s

rule

orderings

t o

observe

t h e i r

e f f e c t s ,

T r a d i t

iona

1

p h o n o l o g i c a l

r u l e s

d e s c r i b e

t r a n s i t i o n s

from

the

u n d e r l y i n g

form

t o

t h e

surface

form o f

a

word.

However,

in

casual

(fast) speech,

words

are

n o t

d i s t i n c t , i n d e p e n d e n t

u n i t s ,

but

r u n

together

a n d

i n t e r a c t .

F a s t

s p e e c h

rules

a t t e ~ p t *-o

d e s c r i b e

t h e s e

c h a n g e s

t h a t

occur

as speech

becomes

f a s t e r

a n d

more

c a s u a l

( 4 ,

8,

9 ) .

T h i s

is

a.

case

# h i s t o r y

of

t h e

examination of

t w o

p a r t i c u l a r

sets of

r u l e s

on

the

P h o n o l o g i c a l

Grammar

Tester

(PGT) of

Friedman

a n d

Borin

(3)

.

An

overview

is

g i v e n

in A p p e n d i x

A

a n d

a

s a m ~ l e

of t h e

output

i n

A p p e n d i x

8.

In

a d d i t i o n

t o

t e s t i n g t h e s e

two

s e t s

of

f a s t

s p e e c h

rules,

we

were

also

i n t e r e s t e d

i n

the

Testing

the

Fast Seeech

Rules

-

-

- - I -- - - C m I I I L I . I .

F o r

our

f

j

c s t t e s t ,

w

chose

t h e

fast

s p e e c h

r u l e s

of

Neu

(6) a s

the

b e s t

a v a i l a b l e

s e t

of

r u l e s

g i v e n

i n

a

r e a s o n a b l y .

c o n s i s t e n t

n o t a t i o n .

The

r u l e s

Mere

g i v e n

in

t w o

formats:

one

u s i d g

phonemes

a n d

t h e

other

u s i n g

d i s t i n c t i v e

f e a t u r e s .

T h e

f i r s t

t a s k was

to

a d j u s t

t h e

n o t a t i o n

i n t o

a

machine

u s a b l e

form.

For

t h e

purposes

of this

t e s t , we used

t h e

feature

s y s t e h

of

Chomsky

a n d

H a l l e

('I),

w i t h

three

t y p e s

of

b o u n d a r i e s : s y l l a b l e

( +

,

morpheme

( 3 )

a n d word

( # I )

.

For example,

t h e

f

eatur'es

a n t e r i o r

---a

and

---

coronal

h a d

to

be

s u b s t i t u t e d

f o r

&ace'

_of

a r t i ~ u 1 a t i . o ~ .

A l s o ,

t h e

r u l e s

h a d

t o

b e

m o d i f i e d

so

t h a t

each

f e a t u r - e had

t h e same

t y p e

of

v a l u e ( i n t e g e r ,

b i n a r y ,

g r

marked-

unmarked)

t h ~ o n g b o u t t h e

grammar.

For

e x a m p l e ,

i n

the

PG?,

l s t r e s s

is

not

e q u a l

to

+ssess

and

is

less t h a n

=stress,

w h i c h

---

f

c o u l d

cause

m a n f

unexpected

p r o b l e m s

i n

the

grammar.

Another

minor

problem

was

aetermining

w h e t h e r

a

C

I

i n

t h e

rules meant

not

----.-- a vo we1

,

I+

consl,

or

up--

v o c a l l .

S a m p l e

d e r i v a t i o n s

were

g i v e n

w i t h

t h e

rules,

and t h e s e .

were

.used as a

f i r s t

t e s t .

We

q u i c k l y

f o u n d

a

number

of

small

p r o b l e m s ,

most

being

t h a t t h e

rule

had

b e e n

incorrectly

or

incompletely

s t a t e d .

For example,

Geminate

R e d u c t i o n

a n d

A l v e o l a r

F l a p p i n g

would

not

a p p l y

across

t h e

word boundary

i n

"want

to",

w h i l e t h e

E

i n

" c a p t a i n 1 v

b l o c k e d t h e

a p p l i c a t i o n

of

lott tali eat ion.

erro-1s

were

f a u n d ,

such

a a

Nasal

Consonant Deletion

b l e e d i n g

T r a n s i t i o n a l

S t o p

I n s e r t i o n

and

thereh

y

i n d i ' c a t i n g

t h a t

it

s h o u l d

be

ordered

a f t e r

Transtop.

W e

s t i l l

had

SOB-e

u n r e s b l

ved

problems,

such

a s

"Ts

/f

e d

a

1/

a

proper

f a s t

s p e e c h form

of

' f . e d e r a l ' ? l g ,

when

t h e

r e v i s i o n s a n d

a d d i t i o n s

(7)

a r r i v e d ,

Many

of

thes

e

r e v i s i o n s corresponded

to

o u r

s o l u t i o n s

of

problems

encoun\telCed

d u r i n g

t e s t f

ng o f

these

r u l e s .

The

f

i a a l form

of

t h i s f i r s t

sot

is

g i v e n

i n

l p p e n d i x

C.

S i n c e

there

was

l i t t l e

o b v i o u s

order

in

the r u l e s ,

g r a p h i n g

the

~ a r t i a l

o r d e r i n g

g i v e n

was

very

h e l p f u l

in

e x p l o r i n g

the

r u l e

o r d e r i n g .

T h e

p a r t i a l o r d e r i n g g i v e n

w i t h

the r u l a s ,

Ficrure

1,

was

q u i c k l y r e f i n e d

t o that

i n

F i g u r e 2

by

t e s t i n g

t h e

s a m p l e

d e r

i

va't

i

cns

.

In

these

n e w

'rules,

p a r t i c u l a r

a t t e n t i o n

was

p a i d

t o

t h e

presence

a n d

p o s i t

i o n

of

s y l l a b l e , a o r p h e n e

a n d

word b o u n d a r i e s

i n

t h e

e n v i r o n m e n t s

for

w h i c h

t h e

r u l e s

s h o u l d a p p l y .

O t h e r

f a s t

speech

rules

from

members.

of

t h e

A R F A

S p e e c h

U n d e r s t a n d i p g

Research

( S U R )

community

(11, 12, 1 3 )

vere

used

3s

references,

e s p e c i a l l y

in

respect

t b

b o u n d a r y

p o s i t i o n ,

i n

i m p l e d e n t i n g f h

ase

new

rules.

In

t e s t i n g

the

r u l e s ,

most

o f

t h e

p r o b l e m s

i n v o l v ' e d

t h e

p o s i t i o n i n g

and poesence

of

b o u n d a r i - e s .

T h e

second

D e n t a l D e l e t i o n

r u l e

was

dropped

from

t h e

grammar

because

it

a p p e a r e d

t c

d u p l i c a t e

the effect

o f

a s s i m i l a t i n g

a n

a l v e o l a r

f l a p p e d

g

t o

the

p r e c e d i n g

5.

G R A P H O F P A R T I A L O R D E R I N G

-

-L I N E A R I Z E D

-....---

SCHWA D E L E T I O N < I N G > R E D U C T I O N

R U H - R E D U C T I O N R U H - L E S S N E S S

N A S A L I Z E D VOWELS N A S A L C O N S O N A N T

EEL

ET I0

N

D E N T A L

DELETION

A L V E O L A R F L A P P I N G

G L O T T A L S T O P FoRHqTIoN

P A L A T A L I Z A T I O N

A

SSI

31 LA

TZO

N

TFiAN S I T I O N A L

STOP

INS E R T I O N

G E K I N A T E REDUCTION

D A R K

[ L J

[ RJ-FLAPPING

F I G U R " 1 I N I T I A L R U L E O R D E R I N G

-L I N E A R I 7 ; E D

---

VOWEL R E D U C T I O N

SCHWA O E L F T I O N

< I k G >

R E D U C T I O N

R U H -

R E D U C T X O N

N A S A L I Z E D V O W Y L S

T R A N S I T I O N A L STOP

I N S E R T I O N

P A L A T A L I Z A T I O Y

A L V E O L A P

F L A P P X

:

!

N

GLOTTAL S T O P

F O R M A T I O N

D E N T A L D E L E T I O N

G E H X

N A T E RS'D U C T I O N

N A S A L C O N S O N A N T

REGBCT I O N

D A R K

[ L ]

G R t A P H O F P 4 R T I : A L O R D E R I N G

--..-.----..---

---

F I G U R E 2 P I N A L RULE

ORD~~~l4

testing

t h e s e

rules

a

major problem

was

i n

d e t e r m i n i n g

wha-t

d i d

and d i d

n o t

c o n s t i t u t e proper

fast speech

forms.

I n

slow

speech,

it

is

f a i r l y

e a s y

to

break

up

the

utterance i n t o

a

sequence

of

p h o n e m e s ,

b u t

i n

f a s t

s p e e c h ,

the

utterance

is

more

c o n t i q u o u s

a n d

it

is

harder

t o

d e c i d e

what

is

a

segment

a n d

wh.ere t h e

segments

b e g i n

a n d

end.

For

example,

t h e

p a l a t a l i z a t i o n

rules

produce t h e f o l l o w i n g

d e r i v a t i o n :

( a )

.

/ d i d # C y u /

b )

.

/ d i # #

yyu/

( c ) .

/ d i t t y u /

We

a r e

n o t

i n c l i n e d

t o

b e l i e v e

t h a t

a n

i n t e r m e d i a t e

form

/ d i d # # Y y u /

exists

b e t w e e n

s t e p s

(a)

a n d

( b )

in

t h i s

d e r i v a t i o n .

I

t h i n k

t h a t

(b)

i s

a

t r u e

i n t e r m e d i a t e

form,

existing

i n

slower,

casual

speech,

but not

i n f a s t

speech.

O u r

b e s t

e v i d e n c e

i n d i c a t e d t h a t

t h e

R U H

i s

t h e

same a s

t h e

s y l l a b i c

"rU

I

t h u s

r a i s i n g

the

p r o b l e m

of

ordering

t h e

S y l l a b i c i z i n g

a n d Ilu

h - r s d u c t i o n

rules.

Are

the

proper

f o r m s

/g

u

v

+-

n

r/

ahd

/ f

e

d

+

r

l/

or,

more likely,

/g

u

v

+

n

r/

0

a n d

/f

e

d

+

r I/?

Q c ,

c o u l d

it

p o s s i b l y

be

/g

u

v

+

n

r/

a n d

/ f e

d + r I./,

w i t h

t h e

S y l l a b i c i z i n g

r u l e n o t

deleting

the

schua, b u t

n a k i n g

it v e r y

short

a n d

p a s s i b l y

devoicing

it?

Another d i s t u r b i n g

r e s u l t

of

t h e

testing

v a s

the a p p l i c a t i o n

of

rules

across deleted

s e g m e n t s .

For

exaaple, after

qqvernqg

has

b e e n

r e d u c e d

to

/ g

u v

+

n

r/,

Proqressive

A s s i m i l a t i o n

applies,

producing

/g

u v

+

m

r/.

Similarly,

----

s a n i t q

---

clause

c l o s i n g

i n

on

a

.fast

speech

form

of

s a n t a

C l a u s .

T h e final

form

of

t h e

second

s e t

of

r u l e s

a n d the o u t p u t

are

given

i n

A p p e n d i x

D

6

Suggested

& d i f i c _ g t i o n s

to

the

PGT

-

---..

-

---I-

T h e

PGT was

w r i t f e n f o r t h e

t e s t i n g

o f

t r a d i t i o n a l

p h ~ n o l o g i c a t

grammars

w h i c h

t a k e

a n u n d e r l y i n g

form

t o

a

Burface

form,

a n d

t h u s

fast

speech

r u l e s

p r e s e n t

s e v e r a l

u n f o r e s e e n

problems.

F a s t

speech

r'ules

do

not

c o n s t i t . u t e

a

c o n p l e k e

grammar,

b u t

a r e

i o s t e a d

i n t e r s p e r s e d ,

among

t h e

t r a d i t i o n a l

r u l e s ,

Ln

p r o d u c i n g

an

i n t e r m e d i a t e

or

s u r f h c e

for^

f o r

i n p u t

to

t h e

grammar,

t h e

use of

d i a c r i t i c s

would

p r a d u c e

2

simpler

a n d

more

econcmical

represent

a

tion

st

t h e

i n p u t

F o r

e x a m p l e ,

i n

the

p r e s e n t

system,

it

is necessary

to

give

a

s e p a r a t e

d e f i n i t i o n

f o r

each

stress

a s s i g n m e n t

for

each

v o w e l ,

i n s t e a d

o f

d e f i n i n g

each

towel

cnce

a n d

a s s i g n i n g

t h e s t r e s s through t h e

use

of

d i a c r i t i c s .

S y l l a b i f i c a t i o n a D p e a r s

to

o c c u r before

some

of

t h e

r u l e s ,

an

d

after

o t h e r s .

TO

a v o i d

h a v i n g

to

i n s e r t ,

r u l e s

for

s y l l a b i f i c a t i o ~ ~

or

h a v i n g

the

r u l e s

p r e c e d i n g s y l l a b i f i c a t i o n

ignore

s y l l a b l e b o u n d a r i e s

i n t h e

i n p u t ,

the

PGT

s h o u l d

h a v e

a

l@human

i n t e r v e n t i o n "

r u l e w h i c h w o u l d a l l o w

the

user

to

c h m g e

WmissingfI

rules.

"Human

interventionn

rules

c o u l d b e u s e d

t o

postFone Q r i t i n g

rules, either

ro

a

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

or i n d e f i n i t e l y

if

the

rules

are

t o o

h a t d

to

write

or

if t h e y

are

& a t s i . d e t h e

scope

of

t h e

problem.

Another

problem

a r i s e s

from

most,

if

not

a l l ,

f a s t

s p z e c h

r u l e s

b e i n g

o p t i o n a l .

T h e

present

system

generates

a

s i n g l e

d e r i v a t i o n

u s i n g

a

ando om

number

g e n e r a t o r

to

d e c i d e

w h e t h e r

or

not- t o

a p p l y o p t i o n a l

rules.

As

a

result,

t o

obtain

a good

b e s t

of the

e f f e c t

o f a n optional rule

i n

t h o

grammar,

we

h a v e t o

do

two

tests,

O h e w i t h

t h e

rule

o b l i g a t o r y

and

one

w i t h o u t

t h e

rule.

With.

a

large number

of

optional r u l e s

o p e r a t i n g

on

a

r r o n - t r i v i a l

set

of

test data,

h a v i n g

to

test

e a c h

possible

rule combination

i n d i v i d u a l l y

would

b e

a-

staggering

t a s k .

A

more

satisfactory

method

w q u l d

be

for

t h e

PGT

to p r o d u c e

a

set

o f

d e r i v a t i o n s s u c h

t h a t

a n y

t i n e

a n

o p t i o n a l

rule

can

a p p l y ,

t h e

PGT

produces

a

d e r i v a t i o n for

t h e

case

where

the.

rule

was

a p p l i e d

a n d

one

f o r

the case

where

it

wasn't.

Cohen

ana

Mercer

(2)

have

i m p l e m e n t e d

s u c h

a

f e a t u r e

i n t h e i r

rule

tester

b y

storing

the

r e s u l t

of the

a p p l i c a t i o n

of

a

r u l e

a s a

directed gra.ph.

S u b s e q u e n t

r u l e s

are

a p p l i e d

t o

a l l

p a t h s t h r o u g h

t h e

g r a p h ,

p r o d u c i n g

a

neu graph.

In

c o n s i d e r i n g

the problem of

when

a n

o p t i o n a l

r u l e

s h o u l d

be

a p p l i e d ,

we

are

c o n s i d e r i n g p g f o u a n c e

(10)

.

To t h i s

end,

we

m i g h t

be b e t t e r

served by

h a v i n g

t h e

v a r i a b l e

r u l e s

of

Iabov

(5)

ia a d d i t i o n

t o t r a d i t i o n a l p h o n o l o g i c a 1

r u l e s .

f

n s t e a d

of

the

a l l -

or-

n o t h i n g

m a t c h i n g

of

normal r u l a s ,

v a r i a b l e

rules employ

a p p l i e d b e i n g

a

f u n c t i o n

of

t h e

degree

o f

match,

t h e

r a t e

o f

speech,

and

the

n a t u r e

of

t h e

c o n v e r s a t i o n

( e , g .

Is

i t

formal

or

c a s u a l ? )

.

For

example,

for:

t h e

Froqrelssive A s s i m i l a t i o n

mile

for

p o i n t

of

articuigtion

(PROARTICJ

,

/ s

O

f

n/

((soften)

becomes

/S (3

f m/

only

i n

v e r y

f a s t speech,

h u t

/ p

r

+

f y

u

+

n/

v N

( p r o f u s i o n )

becomes

/p c +

f

y

u

+ z

n/

i n

sost

f a s t

s p e e c h .

I n

a d d i t i a n ,

f o r

each

v a r i a b l e

rule

a p p l i e d ,

t h e

PGT

s h o u l d

use

the

a s s o c i a t e d p r o b a b i l i

t v

t c

produce

a

E i n a l

p r o b a b i l i t y

f o r

each,

d e r i v a t i o n .

U n f o r t u n a t e l y r

t h e

i l b p l e a e n t a t i o n

of

v a r i a b l e

r u l e s

would

n e c e s s i t a t e

major

c h a n g e s

to t h e

PGT.

C o n v e n i e n t ,

b u t

not

n e c e s s a r y ,

w o u l d

be

t h e

ability

t o

make

a r u l e

" b l i n d w

t o certain

t y p e s

of

n o d e s ,

For

example,

Chomskp

a n d

Halle

(1)

a l l o w

sosle

b o u n d a r y

symbols

t o

be

invisible

t o

t h e i r

phonological

rules.

T n

some

cases,

t h i s

a b i l i t y

m i g h t

be

a b l e

t o

f u l f i l l

t h e

f u n c t i o n

of

a

" h u m a n i n t e r v e n t i o n v r u l e ,

O b s e r v a t

i o n s a b o u t

F a s t

Skeech

R

ules

---.----

---

T e s t i n g

t h e

fast

s p e e c h

r u l e s

led

ta

certain

i n s i g h t s

into

t h e

interactions

of

t h e

r u l e s .

The

most

v e x i n g problems verbe

with

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

of

b o u n d a r i e s .

The use

of

2 ,

&,

a n d

g t

seems

a r t i f i c i a l

a n d

cumhersome,

A

moce n a t u r a l

a p p r o a c h

seems

t o b e

to

a s s i g n

t h e

b o u n d a r i e s

v a r y i n g

degrees

of

$treggf_h,

a n d

t h e n

allow

t h e

p h o n o l c g i c a l

rules

t o

o p e r a t e

on

t h e

s t r e n g t h

assignments.

Consider

t h e problem

of

HJohngs

going

t o

uorkll

where q o i n q

i s

a n

auxiliary

b u t not i n t h e

case

uhere

it

is

t h e

v e r b .

Rather

t h a n h a v i n g the

p h o n o l o g i c a l

rule s e n s i t i v e

to

t h e

s y n t a x ,

-it

seems

much

c l e a n e r

to

h a v e

it

s e n s i t i v e

t p

t h e

b o u n d a r y

strength

between

o

n

a n d

to.

To

t h i s

end,

we must

allow t h e

s y n t a x

t o

i n f l u e n c e

t h e

i n i t i a l

a s s i g n a e n t s

of boundacy

s t r e n g t h .

The

use of

boundary

strengths also

seems

to

s o l v e

t h e

problem,

of

how

boundaries

a r e

r e d u c e d .

For

example,

in

r e d u c i n g

want

to

t o

wanna

s h o u l d

t h e

word

b o u n d a r y

b e

reduced

t o

a

me--- ---I

morpheme

or

a

s y l l a b l e

bounda'ry?

A n o t h e r

ase

of

b o u n d a r y

s t r e n g t h s

m i g h t

be t o

mark

t h e

p o s i t i o n

of

segments

d e l e t e d

fcom a

word

b y

s t r e n g t h e n i n g

t h e

n e i g h b o r i n g

boundaty.

For

e x a m p l e ,

when

governor

---

i s

reduced

to

s v

I

ner,

the

p

is

l e n g t h e n e d ,

i n d i c a t i n g t h e p o s s i b l e

presence

o f

a

stronger

then

normal syllable

b o u n d a r y .

This stronger boundary.

w o u l d

t h e n p r e v e n t

the

from

c h a n g i h g

t h e

g

t o a n

-

m

u n d e r

Progressive

A s s i m i l a t i o n .

An

a l t e r n a t i v e

is

t o

h a r e

a

" s t r o n g

s y l l a b l e w boundary

s y m b o l w h i c h

w o u l d

b e "strongerwq

t h a n

a

"weak

wordm bounaary

symbol,

b u t

t h i s

woulil

be

mdssy

and

u n n a t u r a l .

It

voola

p r o b a b l y

b e

more

productive

t o

represent

f a s t

s p e e c h

forms

w i t h

phonemes

u t i l i z i n g m u l t i - v a l u e d

(1

t h r o u g h

7

i n s t e a d

of

+

a n d

)

f e a t u r e s .

G i v i n g

the segments

l e n g t h

a t t r i b u t e s

would

a l l o w s e g m e n t s

t o

be

d e l e t e d

b y

a

combination

of

r u l e s

which reduce

segment l e n g t h s .

Also,

i n c o n p a r i n g

forms,

a

v e r y

short

seqment

could be

considered

t o

be

d e l e t e d .

w h i c h t h e y

can

a p p l y .

Z w i c k y

(14)

g i v e s e x a m p l e s

a n d

c o u n t e r -

e x a m p l e s

for

v a r i o u s

f a s t

speech

r u l e s ;

However,

it

seems

t h a t

t h e

counter-examples

a r e

words

w h i c h

do

n o t

f t e q u e n t l y

occ,ur

i n

&aqua1

speech,

w h i l e

the

e x a m p l e s

were

common.

This

o o i n t

was

i l l u s t r a t e d when

,

i n a n e a r l y

run,

t h a t

Schva

D e l e t i o n

p r o d u c e d

/k

a e

n

+

g

r

u/

from

'tkangaroow,

A T

first, t h i s

East speech

form

was u n a c c e p t a b l e ,

b u t

w i t h

u s e ,

it

b e c d m e

more

a n d

more

acceptable.

Interestingly

e n o u g h ,

a

s m a l l

r a n d o m

p o l l i n g

s e ; n e d

t o i n d i c a t e

t h a t

this

form is

a c c e p t a b l e

"if

y o u t

re

a n

AUS

t r a l i a n t r

.

T h a t

fast

speech

r u l e s a p p l y

t~

what 1 s

common

i n

the

speaker's

v o c a b u l a r y

is

also

e v i d e n c e d

b y

the

h e a v y

a p p l i c a t i o n

of

f a s t

speech

r u l e s

t o

l o c a l

names.

T h e

similarity

af

the

p a l a t i z a t i o n

r u l e s i n

t h i s f a s t

s p a e c f i

grammar

a n d

i n

n o r m a l F n g l i s h ( 1 ) r a i s e s

t h a

q u e s t i o n

o f

W h a t

a r e

' f a s t s p e e c h

rules?".

If

normal r u l e s are r e s t r i c t e d

v e r s i o n s

of

t h e

more

g e n e r a l

p r o c e s s e s

w h i c h

a l s o

a c c o u n t

for

t h e

P a s t

s p e e c h

forms

(14),

t h e n

we

must

be

c a r e f u l

i n using

slow s p e e c h

s u r f a c e

forms

to

t e s t

t h e fast

s p e e c h

r u l e s .

F o r example,

p a r t

of

the

d a t a

covered

b y

t h e

Schwa Deletion

r u l e

m i g h t

a c t u s l l y

result

from

schwas being *ser&gq

b e t w e e n

c o n s o n a n t s

i n

slow

y o r k was s u p p o r t e d u n d e c

N a t i o n a l S c i e n c e

F o u \ n a a a i i o n

1 3 0 9 , w i t h t h e supervision a n d q u i d a n c ~

of

J o y c e

References

---

sky, Noam G

Y o r r ~ s

H a l l e , The S2gm&-Pattern

of

E2gL~l.&,

rper a n d

Row,

Yew Y o r k , Yew Y o r k , 1 9 6 8

Re P . S . &

R.

L.

Mercer,

Y " e P h o n o l o g i c a l Component o f P

Automat

ic S ~ e e c h - R e c o g n i t i o n

S y s t e m f f , C o n t r i b u t e d

ears.

-

I E F E

Sypl~osium

on

Speech

Recognition,

Lee E r m a n

B , 1 9 7 4

mlan,

J o y c e

a

nd Yve s C h .

n o r i n ,

ghonejhqiial

c;rggmgg

Description,

B

Per:

---

Ra

t u r a l

L a n g u a g e S t u d i e s

No.

9 ,

~ n o t i c s L a b o r a t o r y , The University

of

M i c h i g a n , 1 9 7 1

Ilk

an,

J-oyce, vaCcmpu

ter

Exploration

of

F a s t S p e e c h

Iesm, I E E E

T r a n s a c t i o n s

on

A c o u s t i c s , S p e e c h

a n d

S i g n a l $Zessig.q, A S S P - 2 3 , 1,

F e b r u a r y

1 9 7 5

6.

Neu,

Helene,

"Some

Optional P h o n o l o g i c a l

Rules Occurring

i n

C a s u a l

S

peech",

Speecn

t o m a u n i d a t i o n

Research

Laboratory,

S a n t a

Barbara,

C a l i f o r r i a ,

S U R

Note

9 5 ,

N I C 1 7 6 7 7 ,

J u l y

11, 1973

7 .

Neu,

Helene

anll

Beatrice

O s h i k a ,

* O p t i o h a l

Phonological

Rules

-

Revisions an?

Additions",

Speech Comrnunica

L i o n s

Research

Laboratory,

S a n t a

Barbara,

C a l i f o r n i a ,

SUR

Note

1 2 2 ,

N I C 21717,

February

5.

1974

8.

OIMalley,

Michael H.

a n d

Alan

C o l e ,

' V e s t i n g P h o n o l o g i c a l

R u l e s m , C o n t r i b u t e d Papers

-

I E E E

Symposium

on

S p e a c h

R e c o g n i t i o n ,

Lee

Erman

(ed)

,

1974

9 .

Oshika,

Beatrice

f . ,

Victor

W.

Zue,

Rollin

V.

Weeks a n d

Helene

Neu,

" T h e

Role

of

P h o n o - l o g i c a l

Rules

i n

S p e a c h .

U n d e r s t a n d i n g

Researchd,

IEEE Transactions

on

Acoustics,

Speech

and

Signal P r o c e s s i n g ,

A S S P d 2 3 , 1 ,

F e b r u a r y

1975

10.

Robinson,

J a n e

J,

,

wPerformance

GramatarsM,

Technical

Note

TN

97,

Stanford

Research

I n s t i t u t e ,

197U,

t o 'appear

i n

S-eeech

p r e s e n t e d

at

t h e ,

1 9 7 4

I E E E

R e c o s ~ i ~ ~ I ~ ~ f i e d P a p e r s - -

---

---

---

Syemosi

urn

Acaden

ic

Press

-

7-I

11.

Shockey,

Linda,

u n p u b l i s h e d

collection

of

r u l e s ,

Dept.

o f

Computer

S c i , e n c e ,

C a r n e g i e - M e l l o n

U n i v e r s i t y ,

Pi

t t s b g r g h

,

12,

W e e k s ,

R o l l i n

V.,

'9sDC

P h o n o l o g i c a l

R u l e s w ,

Systems

D ~ ~ e l o p m e n t

C b r p . ,

SUR

Note

t 1 9 , N I C 2 1 4 9 0 ,

J a n u a r y

3 1 ,

1974

13. Zue,

Victor,

W.,

" O p t i o n a l P h o n o l o g i c a l

R u l e s n ,

M I T

L i n c o l n

Laboratory,

L e x i n g t o n ,

Mass.,

SUR

Note

1 2 4 ,

NIC 21952,

F e b ~ u a r y 19, 1974

1 4 . Z w i c k y ,

A r n o l d

N.,

"Note

on

a

~ h o n o l o g i c a l

Hierarchy

i n

Xngl,ishit

,

i n

R.

P.

S t o c k w e l l

a n d

R.

K .

S.

~ a c a u l a y

(eds .)

,

L & h q u i s t

&

C h a n 4 e

and

Gen9ratij.e

Theory,

Indiana

&mend

j x

A

-

U s i n %

t

h e

P

hono&oqjcaJlG

rdmgqg-Tes

ter

-

- -

-

--

----*

In

t h e

PG?,

t h e

phonological

r u l e s

are t r e a t e d

as

a

t r a n s f ormat

ional

grammar

w h i c h

o p e r a t e s

on

t r e e s whose

terminal

n o d e s

are

u s u a l l y phonemes

a n d

b o u n d a r y syabolsb..

Y h i . 1 ~

most

p h o n o l o g i c a l

rules

uill

use

o n l y

these

t e r m i n a l

nodes,

i t m a y be

d e s i t a b l e ,

or

e v e n

necessary, t o h a v e

t h e

rule s e n s i t i v e

to

t h e

s y n t a x ,

w h i c h

c o u l d

indicated

b y

t h e

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

n o a e s .

Trees

can be

l i n e a r i z e d

by

U s i n g

I t < " and l g > v t t o

enclose

a

left

to

r i g h t

l i s t i n g

of sibling

nodes,

such t h a t

a

d e s c r i p t i o n

of

each

noh-term5nal n o d e ' s d e s c e n d a n t s

is

a p p e n d e d

to

its

name.

thus:

becomes

S<A B < D 5 )

C>.

In

d e f i n i n g t h e

grammar,

r u l e s

a r e

stated

i n

one

of

two

foras.

The

more g e n e r a l

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

rule

format

h a s

two

parts:

t h e

s t r u c t u r a l

d e s c r i p t i o n ,

w h i c h must

m a t c h

t h e

tree

e x a c t l y

for

t h e

r u l e

t o

a p p l y ,

and

t h e

s t r u c t u r a l c h a n g e , v h i c h d e s c r i b e s

the e f f e c t

of

t h e

rule

upcn

the tree.

S i n c e

these p h o n o l c g i c a l

rules

use

only

the

immediate

c o n t e x t ,

t h e

S D ' s

b e g i n

a n d

end

w i t h

the

unbounded

skip

symbol

"Xn.

Bounded

s k i p s

a r e

l i n e a r i z e d

b y

p r e f i x i n g t h e s y m b o l

w i t h

its

s e p a r a t i n g

them

w i t h

commas

a n d

e n c l o s i n g

t h e m

i n

p a r e n t h e s e s .

\ n

o p t i o n a l

part

o f

tho

structural

d e s c r i p t i o n

is

e n c l o s e d

in

p a r e n t h e s e s

I

N o d e s

used

in

t h e structural

chang-e

are

referenced

by

an

i n t e g e r

p r e f i x .

If

o n l y

one

node

i s

to be

e r a s e d ,

changed

or

i n s e r t e d ,

t h e

second

form

of

t h e r u l e , w h i c h

resembles

t h a t

t r a d i t i o n a l l y

used

in

p h o n o l o g y ,

c a n

be

used.

Example:

VOWTL

N A S A L I Z A T I O N

TRANS

NASVOW.

sn

'V

( ( # ) )

*

(+CONS

-VOCAL* + N A S A L 1

%.

SC.

( + N A S A L (

NERGEP

I ,

The,rules

can

e i t h e r

b e

o b l i g a t a r y

or

o p t i o n a l a n d

c a n

h a v e

one

of

three

modes

of

a p p l i c a t i o n :

s i n g l e ,

s i m u l t a n e o u s ,

or

r e p e t i t i v e .

The

PGT

also

c o n t a i n s

p r o v i s i o n

for

a

c o n t r o l

program

which

will

d i r e c t

the order

in

w h i c h t h e

rules are

t r i e d ,

w i t h the

d e f a u l t

being

that

t h e

r u l e s are

tried

once

i n

t h e

order

g i v e n .

w i t h

the P G T

has

b e e n

d e v e l o p e d ,

n o r

H a s

a

procedure

for

a c q u i r i n g

an

a p p r o p r i a t e

i n p u t

set.

Our

p r o c e d u r e

has

b e e n

t o

a d j u s t

t h e

g r a m m a r

w h i l e

t r y i n g

to

o b t a i n

the

samplz derivations

Note: e x p l a n a t i o n s

are

in

lower

case.

' ~ 3 : N T E i O D U C Y I O N : l m S<'!lB N < ' f l B

'XI2

'N 'SB

IT

'R

$03

'SB

'D

' U H 1

'K

'SR

' S H

'EH2

'N

'MB>

' M E > *

echoes the

i n p u t

T R E E

R E A D B Y

P T R I N

1

S

2 X

3

N

# #

11/21

N

+

T

R

0131

+

D

U f l / 1 /

K

+

S H

EH/2/ N

# 4

o u t p u t

t h e

form

i n

tree

a n d

linear

form

rltrlr**rk TRANSFORBATIONS

I****

SCAN

C A L L E D

AT

1

I

start scanning

on

top

llSm

node

ANTEST CALLEC FOR

1

" R

E D V O

W

(AACC)

,SD=

2.

RES=

5 .

TOP=

1

:S

attempt

t o

a p p l y

rule

redvow t o

form

AN

TEST

R E T U R N S

**

I * *

r u l e redvov h a s matched once

absenco

of this message i n d i c a t e s

that the

rule

d i d

not

a p p l y

CHBWGE, H l V E CSERCH FOR HERGEF

IN

10

merge

f e a t u r e s

i n t o

node

10

(making

it

a

schwa)

ANTEST CALLED

F O B

211SCFIHDA (AACC)

,

SD=

3.

RES=

7.

TOP= 1 :S

ANTEST CALLED

F O R

3"

SCH

W D B

(AACC)

,SD=

4.

RES=

9 .

TOP=

1 :S

ANTEST CALLEC FOR

U ING

(AACC)

,

SD=

5,

RES=

O 0

TOP.= 1:s

ANTEST CALLED

F O E

SV1SYZLAB

tt (AACC)

,SD=

6.

RES-

11.

TOP=

1 :S

ANTEST RETURNS

**

I * *

CHANGE. CALL ELENOP

FOR

E R A S E

0

17

erase

node

17