Optimality theory
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Optimality theory
April 1998
Optimality theory
UR (underlying representation)
Gen
Candidate Set (1…n)
Select the winner from the candidate set
by means of a tableau.
See word tableau.
Optimality theory: a language specifies a
ranking of constraints; select the optimal
candidate from among the set of
candidates with the following algorithm:
For a given set of candidates, iterate
through the constraints: I=0;
Loop: I= I + 1;
– for constraint I, find the lowest number of
violations V of the constraint I; eliminate all
candidates that violate it more than V
times;
– if more than 1 candidate remains, proceed
through loop again; otherwise, the
remaining candidate is the winner.
Optimality theory
Bare bones, subject to modifications as
needed:
A theory relating underlying forms to
surface form(s).
To each input (=underlying) form,
associate a (potentially infinite)
candidate set, produced by GEN.
Choose the output by means of a tableau.
Alternatively put:
Assign a decimal fraction to each
candidate thusly:
Optimality score: 0.a1 a2 a3 a4 …
where a1 is the number of violations of
the 1st constraint, etc.
If ai is always < 10, then:
the winning candidate is the one with the
lowest optimality score.
Issues and concepts in OT
Constraints are said to be universal, but
nobody acts as if they were a fixed set
from a research point of view. What this
belief means in practice is that we do
not need to think about how they could
be learned
Constraints divide into two important
subgroups: Faithfulness constraints and
phonotactic constraints.
Faithfulness constraints measure the
degree of difference between UR and
SR (surface).
However important that difference is
conceptually, it is not a theoretical
difference: all constraints are ordered in
the same ranking.
Early on, the critical or essential claim of
OT was the strict hierarchical ranking of
constraints: this meant that no coalition
of lower ranked constraints c1, c2 could
get together and be more important
than a single constraint D, if D outranks
C1 and C2 individually.
This is the primary difference between
early OT and harmonic phonology,
and...
This claim was abandoned by Smolensky
in 1995, for constraint conjunction,
which allowed the conjunction of two
constraints to be ranked separately from
(and higher than) either of the
constraints individually.
Yawelmani CV distribution
1. All words: [C
2. *[CC , * CC]
3. *VV
4. *CCC
1. Onset: syllables begin with a consonant
2. Peak: syllables have one („a‟?) vowel
3. NoCoda: syllables end with a vowel.
4. *Complex: syllables have at most one
consonant at an edge.
5. Syllables are composed of consonants
and vowel (Onset & peak).
“general tendencies, not laws.”
Violated in Yawelmani?
Peak: never
Onset: never
*Complex: never
NoCoda: sometimes
The grammar of a language specifies a
language-particular ranking of
constraints.
Faithfulness constraints
Faithfulness constraints require that the
output be identical to the input.
In Yawelmani, “as a violable constraint,
NoCoda must be outranked by some
more important constraint …
Faithfulness…”
How is it that NoCoda could in principle
be satisfied?
Syllabify the consonant in question as a
peak. Xa.ten. -> xa.te.n. English:
meter, metric.
Delete the C in question.
Insert a vowel. Xaten -> xateni.
See Word tableau
More Yawelmani
Xat+ en = xaten
logw+ en = logwen
but
xat+ hin = xathin
logw+ hin = logiwhin. Why? How?
See tableau.
Spanish
absorber absorto *absorbto
esculpir escultor *esculptor
distinguir dintinto *distingto
Spanish deletes the non-coronal
obstruent in a cluster.
English
Permits more complex codas than
Spanish or Yawelmani Yokuts
limpness
softness
crispness
strangeness
Tableau...
More generally
Faithfulness >> Onset, NoCoda
(C)V(C)
Onset, NoCoda >> Faithfulness
CV
Onset>> Faithfulness >> NoCoda
CV(C)
NoCoda>>Faithfulness >> Onset
(C) V
Generalized Alignment
(McCarthy and Prince 1993
Yearbook of Morphology)
Align (category 1, L/R,
category 2, L/R):
Constituent type: could be:
Prosodic word; stress foot; syllable; mora;
For all (L/R) edges of Cat 1, there is a Cat
2 edge of (L/R) (you might think: Cat 1
is bigger than Cat 2 -- but...)
Reference to edge:
Secondary stress on first syllable:
Tátamagouchi, not Tatámaguchi
Tagalog: the affix -um- falls as near as
possible to the left edge of the stem
subject to coda restriction:
u ma ral „teach‟
su mu lat „write‟
gru mad wet „graduate‟
Ulwa: -ka- „his‟ falls immediately after the
head foot of the word:
bás ka „hair‟
siwá ka nak „root‟
English: Align (Prosodic Word, L, Foot, L)
Tagalog: -um- Align ( [um], L, Stem, L)
Ulwa: Align ([ka], L, Foot‟, R) where Foot‟
= head foot.
Align 2 phonological cat’s
Ft-Binarity: Feet must be binary under
syllabic or moraic analysis.
(unviolable)
Trochaic: Ft -> Syllstrong Syllweak
Parse-syll: All syllables must be parsed by
feet.
It follows: parsing is unambiguous in the
case of words of even # of syllables.
Odd number of syllables:
L->R: Wankumara:
á a á a á a = (á a)(á a)(á a)a
R->L Warao
a (á a) (á a) (á a)
Initial dactyl = initial trochee plus R->L
Garawa (á a) a (á a)(á a)
L->R plus final trochee (Polish)
(á a) (á a)(á a) a (á a)
Parse syllable is violated, minimally, in all
these cases.
Garawa:
Main stress falls on initial syllable;
Secondary on the penult;
Tertiary on every other syllable leftward
from the penult, but not on the 2nd.
Garawa
yá mi eye
púnja la white
wá tjim pà ngu armpit
ká ma la rì nji wrist
yá ka lâ ka làmpa loose
ngár ki ri kî rim pà yi fought with
boomerangs
ngá mpa lâng in mûkun jìna „at our many‟
nár ngin mûkkun jîna mìra „at your own
many‟
Garawa
Align Prosodic Word:
Align (ProsodicWord, Left, Foot, Left):
Left edge of each prosodic word must
match the left edge of some foot.
Right edge?
Align Foot:
Align (Ft, R, ProsodicWord, R)
Every foot stands in final position in
PrWd.
Conflict in Trisyllables:
(Ss)S Align PrWd:OK AlignFt:NO
s(Ss) Align PrWd: NO AlignFt: OK
In general, minimal violation, together with
Align Ft, means squeezing the singleton
(nonfooted) syllable to the “opposite”
side.
See Word page.
Other rankings to yield trochees:
Left to right:
Align (Foot, L, PrWd, L) >>
Align (PrWd, R, Ft, R)
Right to Left
Align (Foot, R, PrWd, R) >>
Align (PrWd, L, Ft, L)
More...
Initial dactyl:
Align (PrWd, L, Ft, L) >>
Align (Fot, R, PrWd, R);
Left to Right plus Final Trochee
Align (PrWd, R, Ft, R) >>
Align (Ft, L, PrWd, L)
Non-iterative stress assignment
If Alignment >> Parse-syllable, then we
get non-iterative footing:
see Word:
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