Learning Long Distance Phonotactics Jeffrey Heinz heinz@udel.edu - - PowerPoint PPT Presentation

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Learning Long Distance Phonotactics Jeffrey Heinz heinz@udel.edu - - PowerPoint PPT Presentation

Learning Long Distance Phonotactics Jeffrey Heinz heinz@udel.edu University of Delaware University of Chicago Workshop June 12, 2008 J. Heinz (1) (University of Delaware) Learning Long Distance Phonotactics June 12, 2008 1 / 67


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SLIDE 1

Learning Long Distance Phonotactics

Jeffrey Heinz heinz@udel.edu

University of Delaware

University of Chicago Workshop June 12, 2008

  • J. Heinz (1) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 1 / 67

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SLIDE 2

Introduction

I present a learner which learns the attested long distance phonotactic patterns in the world’s languages This learner

(1) keeps track of the order of sounds—but not the distance between them (precedence relations) (2) fails to learn logically possible—but unattested—long distance phonotactics

The conclusion is if humans generalize in the way suggested by the model, it can explain features of the typology of long distance phonotactics (cf. Moreton 2008, analytic bias)

  • J. Heinz (2) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 2 / 67

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SLIDE 3

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (3) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 3 / 67

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SLIDE 4

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (4) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 4 / 67

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SLIDE 5

What is long distance phonotactics (LDP)?

Long Distance Agreement (LDA) patterns are those within which particular segments, separated by at least one other segment, must (dis)agree in some feature (Hansson 2001, Rose and Walker 2004). Hansson (2001) adds that the intervening segments are not audibly affected by the agreeing feature. This is in order to clearly distinguish LDA from spreading (see also Gafos 1999 and Walker 1998).

  • J. Heinz (5) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 5 / 67

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SLIDE 6

Symmetric LDA: Navajo (Athabaskan)

In well-formed words, sibilants agree in the feature [anterior]. 1. [s,z,ts,ts’,dz] never precedes [S,Z,tS,tS’,dZ]. 2. [S,Z,tS,tS’,dZ] never precedes [s,z,ts,ts’,dz]. Examples (Sapir and Hojier 1967): 1. Si:te:Z ‘we (dual) are lying’ 2. dasdo:lis ‘he (4th) has his foot raised’ 3.

∗Si:te:z

(hypothetical) 4.

∗dasdo:liS

(hypothetical)

  • J. Heinz (6) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 6 / 67

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SLIDE 7

Asymmetric LDA: Sarcee (Athabaskan)

In well-formed words, sibilants agree in the feature [anterior], but only the [-anterior] sibilants are ‘active’. 1. [s,z,ts,dz] never precedes [S,Z,tS,dZ]. Examples (Hansson 2001, citing Cook 1979,1984): 1. S´ ıtS´ ıdz` aP ‘my duck’ 2. n¯ aSG´ atS ‘I killed them again’ 3. *z´ ıtS´ ıdz` aP (hypothetical) 4. *sn¯ aSG´ atS (hypothetical)

  • J. Heinz (7) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 7 / 67

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SLIDE 8

Examples of long distance phonotactics

Consonantal Harmony (Hansson 2001, Rose and Walker 2004)

  • Sibilant, liquid, dorsal, voicing, ...harmony and disharmony
  • Symmetric/Asymmetric LDA
  • ∼120 languages documented with consonantal harmony (Hansson 2001).

possibly Vowel Harmony with ‘transparent’ vowels

  • Finnish, Hungarian, Nez Perce (see Bakovi´

c 2000 and references therein)

  • Some controversy over how transparent: see Gordon (1999), Gafos and

Benus (2003), and Gick et. al. (2006).

  • J. Heinz (8) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 8 / 67

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SLIDE 9

One debate, two puzzles

Debate: Is it really non-local? Puzzles

  • How do we explain the absence of blocking in the typology?
  • (if it non-local) How such non-local patterns learned?
  • J. Heinz (9) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 9 / 67

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SLIDE 10

Debate: Is LDP really spreading?

Spreading means the intervening segments are affected. Nasal spreading in Malay (Johore dialect, Walker 1999, citing Onn 1980) 1. m˜ @n˜ a˜ w˜ an ‘to capture’ (active) 2. p@N˜ a˜ w˜ asan ‘supervision’ Navajo’ as spreading (+/- indicates [anterior]) 3. Si ¯:t ¯e ¯:Z ‘we (dual) are lying’ 4. dasd ffo ff:l ffi ffs ‘he (4th) has his foot raised’ Gafos (1999) argues that Navajo=Navajo’ (see Hansson 2001 for counterarguments).

  • J. Heinz (10) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 10 / 67

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SLIDE 11

Debate: Is LDP really spreading?

Spreading means the intervening segments are affected. Nasal spreading in Malay (Johore dialect, Walker 1999, citing Onn 1980) 1. m˜ @n˜ a˜ w˜ an ‘to capture’ (active) 2. p@N˜ a˜ w˜ asan ‘supervision’ Navajo’ as spreading (+/- indicates [anterior]) 3. Si ¯:t ¯e ¯:Z ‘we (dual) are lying’ 4. dasd ffo ff:l ffi ffs ‘he (4th) has his foot raised’ Gafos (1999) argues that Navajo=Navajo’ (see Hansson 2001 for counterarguments).

  • J. Heinz (11) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 10 / 67

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SLIDE 12

Puzzle # 1: Explaining the typology of LDP

The typology of LDA is notable in two respects (Hansson 2001, Rose and Walker 2004):

(1) LDA holds between similar segments. (2) Blocking patterns are absent.

The latter helps distinguish LDA from spreading.

  • J. Heinz (12) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 11 / 67

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SLIDE 13

LDP with Blocking: Hypothetical

In well formed words, voiceless sibilants agree in the feature [anterior] unless, between two voiceless sibilants which disagree in [anterior], there is a voiced sibilant (and no other voiceless sibilants). 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Examples (all hypothetical since no language example exists!): 1. SotoS 3. Sozos 5. *Sotos 7. *Sosozos 2. sotos 4. sosozoS 6. *sotoS 8. *soSosozos

  • J. Heinz (13) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 12 / 67

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SLIDE 14

LDP with Blocking is Unattested

The absence of this type of LDP is robust! Consenus has formed in the few proposed counterexamples (Sanskrit, Kinyarwanda) that they are better analyzed as spreading (Schein and Steriade 1986, Mpiranya and Walker 2005).

  • J. Heinz (14) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 13 / 67

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SLIDE 15

Current Proposal Explaining The Typology of LDP

Rose and Walker (2004) take both gaps as systematic. Their Agreement By Correspondence (ABC) analysis of LDA in OT uses:

CC-Correspondance constraints: two consonants are in correspondence if they are sufficiently similar (agnostic about similarity metric) ID-CC(FEATURE) constraints which enforce agreement of FEATURE for corresponding consonants.

This is intended to capture both the similarity and blocking effects.

  • J. Heinz (15) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 14 / 67

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SLIDE 16

But it fails. . . hence Puzzle #1

Hansson (2007) studies the predicted typology of ABC and shows the ABC approach does predict non-local blocking effects of certain types. . . . reluctantly suggests that the absence of blocking patterns is accidental.

  • J. Heinz (16) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 15 / 67

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SLIDE 17

But it fails. . . hence Puzzle #1

Hansson (2007) studies the predicted typology of ABC and shows the ABC approach does predict non-local blocking effects of certain types. . . . reluctantly suggests that the absence of blocking patterns is accidental. Current theory doesn’t explain the absence of blocking in the typology of LDP

  • J. Heinz (17) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 15 / 67

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SLIDE 18

Puzzle # 2: Learning LDP

Arbitrarily many segments may intervene between agree-ers. Albright and Hayes (2003a) observe that “the number of logically possible environments. . . rises exponentially with the length of the string.” Thus there are potentially too many environments for a learner to consider in discovering LDP patterns.

  • J. Heinz (18) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 16 / 67

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SLIDE 19

The Meaning of “arbitrarily many”

However, does “arbitrarily many” really require a learner to consider every logically possible nonlocal environment?

  • J. Heinz (19) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 17 / 67

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SLIDE 20

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (20) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 18 / 67

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SLIDE 21

Phonotactics as sets

The possible words of English can be thought of a set which includes: { slam, fist, blick, flump, . . . } and which excludes: { sram, fizt, bnick, flumk, . . . }

  • J. Heinz (21) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 19 / 67

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Phonotactics as sets

The binary, categorical distinction between ‘well-formed’ and ‘ill-formed’ is a convenient abstraction. kIp > Twi:ks > bzArSk (Coleman and Pierrehumbert 1997, Frisch, Pierrehumbert and Cole 2004, Albright and Hayes 2003, Kirby and Yu 2007, Hayes and Wilson 2008)

  • J. Heinz (22) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 19 / 67

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What kind of sets are long distance phonotactic sets?

word Navajo Sarcee Hypothetical to

  • sotos
  • SotoS
  • Sotos

×

  • ×

sotoS × × × Sozos ×

  • sozoS

× ×

  • soSozoS

× × × . . .

  • J. Heinz (23) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 20 / 67

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SLIDE 24

What kind of sets are long distance phonotactics?

Long distance phonotactic patterns are regular.

[Johnson(1972), Kaplan and Kay(1981), Kaplan and Kay(1994), Ellison(1992), Eisner(1997), Albro(1998), Albro(2005), Karttunen(1998b), Frank and Satta(1998), Riggle(2004), Karttunen(2006)]

Regular sets have many characterizations (see e.g. Kracht 2003). They are those sets describable with:

finite state acceptors right-branching rewrite grammars regular expressions monadic second order logic

  • J. Heinz (24) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 21 / 67

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SLIDE 25

Finite State Acceptors

FSAs (1) can be related to finite state OT and rule-based models, which allow us to compute a phonotactic finite-state acceptor (Johnson 1972, Kaplan and Kay 1994, Karttunnen 1998, Riggle 2004), which becomes the target grammar for the learner. (2) are well-defined and can be manipulated. (Hopcroft et. al. 2001).

  • J. Heinz (25) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 22 / 67

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Symmetric LDP: Navajo

1. [s,z,ts,ts’,dz] never precedes [S,Z,tS,tS’,dZ]. 2. [S,Z,tS,tS’,dZ] never precedes [s,z,ts,ts’,dz].

C,V

1

s

2

C,V s C,V

S S

C = any consonant except sibilants s = [+anterior] sibilants V = any vowel S = [-anterior] sibilants Accepts Rejects sos soS SoS Sos sots Stos SotoS ... ...

  • J. Heinz (26) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 23 / 67

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SLIDE 27

The FSA Representation of Navajo Sibilant Harmony

C,V

1

s

2

C,V s C,V

S S This grammar recognizes an infinite number of legal words, just like the generative grammars of earlier researchers. It does accept words like [tnSSSSttttttSiiii]—but this violates other constraints on well-formedness (e.g. syllable structure constraints). If the OT analyses of LDA given in Hansson (2001) or Rose and Walker (2004) were written in finite-state terms, this acceptor is exactly the one returned by Karttunen’s (1998) and Riggle’s (2004) algorithms.

  • J. Heinz (27) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 24 / 67

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SLIDE 28

Asymmetric LDP: Sarcee

1. [s,z,ts,dz] never precedes [S,Z,tS,dZ].

C,V

1

s C,V s

S

C = any consonant except sibilants s = [+anterior] sibilants V = any vowel S = [-anterior] sibilants Accepts Rejects sos soS SoS SosoS Sots stoS SoSos ... ...

  • J. Heinz (28) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 25 / 67

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LDP with Blocking: Hypothetical

1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S]

C,V,z

1

s

2

z C,V s z C,V

S S

C = any consonant except sibilants s = [+anterior] voiceless sibilants V = any vowel S = [-anterior] voiceless sibilants z = any voiced sibilant Accepts Rejects sos soS SoS Sos Sotozotos StozoSos . . . . . .

  • J. Heinz (29) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 26 / 67

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SLIDE 30

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (30) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 27 / 67

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SLIDE 31

Learning in Phonology

Learning in Optimality Theory

[Tesar(1995), Boersma(1997), Tesar(1998), Tesar and Smolensky(1998), Hayes(1999), Boersma and Hayes(2001), Lin(2002), Pater and Tessier(2003), Pater(2004), Prince and Tesar(2004), Hayes(2004), Riggle(2004), Alderete et al.(2005)Alderete, Brasoveanua, Merchant, Prince, and Tesar, Merchant and Tesar(2006), Wilson(2006), Riggle(2006), Tessier(2006)]

Learning in Principles and Parameters

[Wexler and Culicover(1980), Dresher and Kaye(1990), Niyogi(2006), Pearl(2007)]

Learning Phonological Rules

[Gildea and Jurafsky(1996), Albright and Hayes(2002), Albright and Hayes(2003a), Albright and Hayes(2003b)]

Learning Phonotactics [Ellison(1992), Goldsmith(1994), Frisch(1996), Coleman and Pierrehumbert(1997),

Frisch et al.(2004)Frisch, Pierrehumbert, and Broe, Albright(2006), Goldsmith and Xanthos(2006), Heinz(2007), Hayes and Wilson(2008), Goldsmith and Riggle(submitted)]

  • J. Heinz (31) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 28 / 67

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SLIDE 32

Identification in the Limit from Positive Data (Gold 1967)

Learner Grammar G Language Language

  • f G

Sample Grammar

  • f

G′ G′

What is Learner so that Language of G’ = Language of G?

See Nowak et. al. (2002) and Niyogi (2006) for overviews.

  • J. Heinz (32) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 29 / 67

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SLIDE 33

Inductive Learning and the Hypothesis Space

Learner Grammar G Language Language

  • f G

Sample Grammar

  • f

G′ G′

Learning cannot take place unless the hypothesis space is restricted. G’ is not drawn from an unrestricted set

  • f possible grammars.

The hypotheses available to the learner ultimately determine:

(1) the kinds of generalizations made (2) the range of possible natural language patterns

Under this perspective, Universal Grammar (UG) is the set of available hypotheses.

  • J. Heinz (33) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 30 / 67

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SLIDE 34

Different Kinds of Hypothesis Spaces are Learned Differently.

The set of syntactic hypotheses available to children is not the same as the set of phonological hypotheses available to children.

  • The two domains do not have the same kind of patterns and so we expect

them to have different kinds of learners.

Likewise, the set of LDP patterns are different from patterns which restrict the distribution of adjacent, contiguous segments.

  • J. Heinz (34) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 31 / 67

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SLIDE 35

Factoring the Phonotactic Learning Problem

Different kinds of phonotactic constraints can be learned by different learning algorithms. A complete phonotactic learner is a combination of these different learning algorithms Here, I am only showing how one part of the whole learner—the part that learns long-distance constraints—can work.

  • J. Heinz (35) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 32 / 67

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SLIDE 36

Some concerns regarding identification in the limit from positive data

No noise in input No requirement for learner to be efficient No requirement on ‘small’ sample to succeed Exact identification is too strict a criterion

  • J. Heinz (36) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 33 / 67

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SLIDE 37

The Learning Question in Context

Symmetric LDP (Navajo) C,V

1

s

2

C,V s C,V S S Asymmetric LDP (Sarcee)

C,V

1

s C,V s

S What learner can acquire the machines above from finite samples of Navajo, Sarcee, respectively? This question is not easy. There is no simple ‘fix’. The class of regular sets is known to be insufficiently restrictive for learning to occur! (Gold 1967, Osherson et. al. 1986, Jain et. al. 1999).

  • J. Heinz (37) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 34 / 67

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SLIDE 38

The Learning Question in Context

Symmetric LDP (Navajo) C,V

1

s

2

C,V s C,V S S Asymmetric LDP (Sarcee)

C,V

1

s C,V s

S What learner can acquire the machines above from finite samples of Navajo, Sarcee, respectively? This question is not easy. There is no simple ‘fix’. The class of regular sets is known to be insufficiently restrictive for learning to occur! (Gold 1967, Osherson et. al. 1986, Jain et. al. 1999).

  • J. Heinz (38) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 34 / 67

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SLIDE 39

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

Some subclasses of the regular languages are sufficiently restrictive for learning to occur

  • Locally k-testable in the strict sense (Strictly Local)
  • Locally k-testable
  • Many others from grammatical inference community

Angluin(1982), Garcia et al.(1990), Muggleton(1990), Denis et al.(2002), Fernau(2003)

  • J. Heinz (39) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 35 / 67

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SLIDE 40

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Locally 2-testable in the strict sense (Strictly Local) sotos ∈ L iff {so, ot, to, os} ⊆ GL E.g. bigrams

  • J. Heinz (40) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 36 / 67

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SLIDE 41

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Locally 2-testable in the strict sense (Strictly Local) sotos ∈ L iff {so, ot, to, os} ⊆ GL E.g. bigrams Locally 2-testable sotos ∈ L iff {so, ot, to, os} ∈ GL E.g sets of bigrams

  • J. Heinz (41) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 36 / 67

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SLIDE 42

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Locally 2-testable in the strict sense (Strictly Local) sotos ∈ L iff {so, ot, to, os} ⊆ GL E.g. bigrams Locally 2-testable sotos ∈ L iff {so, ot, to, os} ∈ GL E.g sets of bigrams Noncounting there is some n > 0, for all uvnw ∈ L iff uvn+1w ∈ L for all strings u, v, w ∈ Σ∗. E.g. closure of Locally Testable class under concatenation and boolean

  • perations.
  • J. Heinz (42) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 36 / 67

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SLIDE 43

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Spreading Symmetric LDP Asymmetric LDP LDP with Blocking

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

Spreading is locally 2-testable in the strict sense Symmetric LDP is locally 1-testable Asymmetric LDP and Hypothetical are noncounting

  • J. Heinz (43) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 37 / 67

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SLIDE 44

The Sub-regular Hierarchy (McNaughton and Papert 1971, Pullum and Rogers 2007)

Spreading Symmetric LDP Asymmetric LDP LDP with Blocking

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

The goal!

  • J. Heinz (44) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 37 / 67

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SLIDE 45

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (45) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 38 / 67

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SLIDE 46

Discontiguous Ordered Strings

Order matters, but not distance. Whitney and Berndt(1999), Whitney(2001), Schoonbaert and Grainger(2004), and Grainger and Whitney(2004) use discontiguous

  • rdered strings of length two in a model for reading comprehension

Shawe-Taylor and Christianini (2005, chap. 11) also discuss kernels defined over discontigouous, ordered strings for use in text classification

  • J. Heinz (46) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 39 / 67

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SLIDE 47

Recalling How We Can Describe Symmetric LDP: Navajo

1. [s,z,ts,ts’,dz] never precedes [S,Z,tS,tS’,dZ]. 2. [S,Z,tS,tS’,dZ] never precedes [s,z,ts,ts’,dz].

  • J. Heinz (47) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 40 / 67

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SLIDE 48

Recalling How We Can Describe Symmetric LDP: Navajo

1. [s,z,ts,ts’,dz] never precedes [S,Z,tS,tS’,dZ]. 2. [S,Z,tS,tS’,dZ] never precedes [s,z,ts,ts’,dz]. = [s] can be preceded by [s]. [s] can be preceded by [t]. . . . [t] can be preceded by [s]. . . . [S] can be preceded by [S]. [S] can be preceded by [t]. . . .

  • J. Heinz (48) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 40 / 67

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SLIDE 49

Precedence Grammars

A precedence grammar is a list of the allowable precedence relations in a language.

  • J. Heinz (49) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 41 / 67

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SLIDE 50

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (50) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

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SLIDE 51

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (51) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

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SLIDE 52

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (52) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

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SLIDE 53

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (53) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

slide-54
SLIDE 54

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (54) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

slide-55
SLIDE 55

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos.

  • J. Heinz (55) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

slide-56
SLIDE 56

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos. (2) The Language of G excludes sotoS.

  • J. Heinz (56) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

slide-57
SLIDE 57

Languages Recognized by Precedence Grammars

Words recognized by a precedence grammar are those for which every precedence relation is in the grammar.

  • Example. (Assume Σ = {s,S,t,o}.)

Precedence G =        (s,s) x (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . (1) The Language of G includes sotos. (2) The Language of G excludes sotoS.

  • J. Heinz (57) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 42 / 67

slide-58
SLIDE 58

Precedence Languages are Regular.

These grammars are notational variants. Symmetric LDP (e.g. Navajo) t,o

1

s

2

t,o s t,o S S Precedence Grammar G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . See Heinz (2007) on how to write a finite-state acceptor given a precedence grammar.

  • J. Heinz (58) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 43 / 67

slide-59
SLIDE 59

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (59) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-60
SLIDE 60

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =               . Sample = { } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (60) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-61
SLIDE 61

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =        (s,s) (s,o) (t,s) (t,o) (o,s) (o,o)        . Sample = { tosos } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (61) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-62
SLIDE 62

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =        (s,s) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (62) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-63
SLIDE 63

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , stot } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (63) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-64
SLIDE 64

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , stot } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (64) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-65
SLIDE 65

Learning Precedence Grammars: Navajo Fragment

Navajo Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. 2. [S] never precedes [s]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , stot } The learner has already generalized; it accepts [SoS], [Stot], [sototos] but not words like [Stos] or [sosoS]

  • J. Heinz (65) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 44 / 67

slide-66
SLIDE 66

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Precedence G =        (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (66) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-67
SLIDE 67

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =               . Sample = { } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (67) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-68
SLIDE 68

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =        (s,s) (s,o) (t,s) (t,o) (o,s) (o,o)        . Sample = { tosos } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (68) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-69
SLIDE 69

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =        (s,s) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (69) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-70
SLIDE 70

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , Stots } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (70) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-71
SLIDE 71

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , Stots } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (71) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-72
SLIDE 72

Learning Precedence Grammars: Sarcee Fragment

Sarcee Fragment. (Assume Σ = {s,S,t,o}.) 1. [s] never precedes [S]. Learning Precedence G =        (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o)        . Sample = { tosos , SotoS , Stots } The learner has already generalized; it accepts [SoS], [Stot], [sototos], [Sotos] but not words like [sosoS]

  • J. Heinz (72) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 45 / 67

slide-73
SLIDE 73

Local Summary

Any symmetric or asymmetric LDP pattern (e.g. Navajo and Sarcee) can be described with a precedence grammar. Any symmetric or asymmetric LDP pattern can be learned efficiently in the manner described above.

  • J. Heinz (73) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 46 / 67

slide-74
SLIDE 74

Why Learning LDP is Simple

The number of logically possible nonlocal environments increases exponentially with the length of the word. Precedence-based learners do not consider every logically possible nonlocal environment. They cannot learn logically possible nonlocal patterns like:

(1) If the third segment after a sibilant is a sibilant, they must agree in [anterior]. (2) If the second, third, or fifth segments after a sibilant is a sibilant, they must agree in [anterior]. (3) and so on

  • J. Heinz (74) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 47 / 67

slide-75
SLIDE 75

Locality and LDP

Precedence-based learners do not distinguish on the basis of distance at all. In one sense, every segment is adjacent to every preceding segment. The notion of “arbitrarily many may intervene”—not being able to count distance, while keeping track of order—is sufficiently restrictive for learning to occur.

  • J. Heinz (75) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 48 / 67

slide-76
SLIDE 76

Locality and LDP

Precedence-based learners do not distinguish on the basis of distance at all. In one sense, every segment is adjacent to every preceding segment. The notion of “arbitrarily many may intervene”—not being able to count distance, while keeping track of order—is sufficiently restrictive for learning to occur.

  • J. Heinz (76) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 48 / 67

slide-77
SLIDE 77

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =                       . Sample = { } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (77) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-78
SLIDE 78

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =            (s,s) (s,o) (t,s) (t,o) (o,s) (o,o)            . Sample = { tosos } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (78) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-79
SLIDE 79

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =            (s,s) (s,o) (S,S) (S,t) (S,o) (t,s) (t,S) (t,o) (o,s) (o,S) (o,t) (o,o)            . Sample = { tosos , SotoS } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (79) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-80
SLIDE 80

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =            (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (S,z) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o) (o,z) (z,s) (z,o)            . Sample = { tosos , SotoS , Sozos } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (80) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-81
SLIDE 81

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =            (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (S,z) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o) (o,z) (z,s) (z,o)            . Sample = { tosos , SotoS , Sozos } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (81) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-82
SLIDE 82

The Precedence Learner cannot learn LDP with blocking

Hypothetical Fragment. (Assume Σ = {s,S,t,o,z}.) 1. [S] never precedes [s] unless, for each [S], a [z] or [Z] occurs be- tween [S] and its nearest following [s] 2. [s] never precedes [S] unless, for each [s], a [z] or [Z] occurs be- tween [s] and its nearest following [S] Learning Precedence G =            (s,s) (s,t) (s,o) (S,s) (S,S) (S,t) (S,o) (S,z) (t,s) (t,S) (t,t) (t,o) (o,s) (o,S) (o,t) (o,o) (o,z) (z,s) (z,o)            . Sample = { tosos , SotoS , Sozos } The learner has failed to learn Hypothetical! E.g. it accepts [Sos].

  • J. Heinz (82) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 49 / 67

slide-83
SLIDE 83

Main Conclusion

Spreading Symmetric LDP Asymmetric LDP LDP with Blocking

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

If humans generalize in the way suggested by the precedence learner, it explains why

(1) there are long-distance phonotactic patterns (2) there are no long-distance phonotactic with blocking patterns

  • J. Heinz (83) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 50 / 67

slide-84
SLIDE 84

Main Conclusion

Phonotactics Long Distance = Precedence Languages Spreading Symmetric LDP Asymmetric LDP LDP with Blocking

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

If humans generalize in the way suggested by the precedence learner, it explains why

(1) there are long-distance phonotactic patterns (2) there are no long-distance phonotactic with blocking patterns

  • J. Heinz (84) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 50 / 67

slide-85
SLIDE 85

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (85) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 51 / 67

slide-86
SLIDE 86

Why not just use n-grams over tiers?

(1) Phonologists often employ tiers, also called projections, in their analyses of long distance phenomenon (Goldsmith 1976, 1990, Prince 1984, Hayes and Wilson 2008, Goldsmith and Riggle, un- der review).

  • E.g. vowel tiers, consonant tiers, sibilant tiers

S Z ↑ ↑ S i: t e: Z ‘we (dual) are lying’

  • J. Heinz (86) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 52 / 67

slide-87
SLIDE 87

Bigram learning over tiers learns LDP with Blocking

Consider a word from Hypothetical. s z S ↑ ↑ ↑ s

  • t
  • z
  • S

(hypothetical) Maybe only project voiceless sibilants in this case? What is the theory of tiers? Cf.

  • Rose and Walker’s agnosticism about what is appropriate similarity metric
  • Hayes and Wilson’s antecedently given tiers

but see also Goldsmith and Xanthos (2006)

  • J. Heinz (87) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 53 / 67

slide-88
SLIDE 88

Learning Gradient Phonotactics

(2) Phonotactic patterns are gradient; this is categorical. Nothing in the design on the model depends on its categorical nature. There are many ways to make the model gradient:

  • minimum distance length (Ellison 1994), Bayes law (Tenenbaum 1999,

Goldwater 2006), maximum entropy (Goldwater and Johnson 2003, Hayes and Wilson 2008), kernel methods (Shawe-Taylor and Christianini 2005), and approaches inspired by Darwinian-like processes (Clark 1992, Yang 2000)

  • J. Heinz (88) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 54 / 67

slide-89
SLIDE 89

Learning Gradient Phonotactics

Nothing in the design on the model depends on its categorical nature. precedes s S t

  • s

0.01 . . . S 0.01 t . . . ...

  • Compute cells by calculating the joint probability over precedence

relations

  • Compute cells by calculating conditional probability of a segment (given

all preceding segments) evaluate utility of precedence model with MDL (Goldsmith and Riggle, under review)

  • J. Heinz (89) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 55 / 67

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SLIDE 90

Learning with a Noisy Sample

(3) Can Precedence Learning occur in the presence of noise?

  • a. What if certain precedence relations are not in the sample?
  • b. What if there are just a few exceptions to the constraint?

Angluin and Laird (1988) show that there are classes of languages which, under certain noisy conditions, which can be “probably approximately correctly” learned (Valiant 1984, Kearns and Vazirani 1994). Precedence languages are such a class. It remains to be seen exactly what the precedence learner which handles noise looks like.

  • J. Heinz (90) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 56 / 67

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SLIDE 91

Learning Phonetically Unmotivated LDP Patterns.

(4) Precedence Learning can learn ‘unmotivated’ LDP patterns. E.g. “[b] never precedes [Z].” What do people do? Independently motivated restrictions can be built into this grammar to further restrict the hypothesis space.

  • Similarity restrictions on potential agree-ers (Hansson 2001, Rose and

Walker 2004) (See also Frisch et. al. 2004)

  • Relevency Conditions on interveners (Jensen 1974) (See also Odden

1994).

Use the independently motivated theory of similarity to set Bayesian priors over the precedence-based hypothesis space

  • J. Heinz (91) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 57 / 67

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SLIDE 92

This independence is a good thing

Other models require independently motivated theory of similarity (OT-CC, tiers) Here, such a theory is not needed for learning Allows us to study these factors independently What is the contribution of sound similarity to learning phonological patterns?

  • J. Heinz (92) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 58 / 67

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SLIDE 93

Outline

1

Introduction Long Distance Phonotactics Representing Long Distance Phonotactics

2

Precedence-based Learning Learning in Phonology Precedence Grammars

3

Conclusion Issues Summary

  • J. Heinz (93) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 59 / 67

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SLIDE 94

Summary

A learner which keeps track of order—and not distance— (i.e. precedence relations) learns attested long distance phonotactics, and explains a key feature of the typology—absence of blocking. This helps explain why LDP is distinct from spreading. We ought to investigate

  • How successful as grammars w.r.t MDL
  • How to integrate similarity
  • Whether predictions are confirmed by language acquisition studies
  • J. Heinz (94) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 60 / 67

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SLIDE 95

Acknowledgements

Phonotactics Long Distance = Precedence Languages Spreading Symmetric LDP Asymmetric LDP LDP with Blocking

Regular

Strictly Local Locally Testable Non−Counting

(Locally Testable w/ order)

Thank You.

Thanks to Jim Rogers and Ed Stabler for helpful discussion. I also thank audiences of the U. of Delaware’s Lingustics Spring 2008 Colloquium series and the U. of Delaware’s Cognitive Science Brown-Bag series.

  • J. Heinz (95) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 61 / 67

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SLIDE 96

LDP with Local Blocking: Ineseño Chumash

In well formed words: 1. [S] is never preceded by [s]. 2. [s] is never preceded by [S] unless the nearest preceding [S] is immediately followed by [n,t,l]. Examples (Applegate 1972, Poser 1982): 1. ksunonus ‘I obey him’ 5. Stijepus ‘he tells him’ 2. kSunotS ‘I am obedient’ 6.

∗sustimeS

(hypothetical) 3.

∗ksunonuS

(hypothetical) 7. SiSlusisin ‘they (dual) are 4. kSunots (hypothetical) gone awry’

  • J. Heinz (96) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 62 / 67

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SLIDE 97

LDP with Local Blocking and Precedence Grammars: Chumash

1. [S] is never preceded by [s]. 2. [s] is never preceded by [S] unless the nearest preceding [S] is immediately followed by [n,t,l]. Precedence Grammars as given cannot describe the pattern in Chumash.

∗kSinots

(hypothetical) Stijepus ‘he tells him’ Next I will show how to extend precedence grammars to capture patterns like those found in Chumash.

Bigram Precedence Relative Precedence

  • J. Heinz (97) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 63 / 67

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SLIDE 98

Bigram Precedence

The grammar contains elements of the form (ab,c): “[c] can be preceded by [ab]”. The idea is that in Chumash (St,s) is in the grammar, but (Si,s) is not.

∗kSinots

(hypothetical) Stijepus ‘he tells him’

  • J. Heinz (98) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 64 / 67

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SLIDE 99

Relative Precedence

[ab] relatively precedes [c] iff

(1) [ab] precedes [c] and (2) no [a] intervenes between [ab] and [c]

The second conjunct captures the “nearest-preceding” aspect of the Chumash description above. SiSlusisin ‘they (dual) are gone awry’ [Si] precedes [s] but [Si] does not relatively precede [s] Thus local blocking is achieved by not including (Si,s) in the grammar but including (St,s).

  • J. Heinz (99) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 65 / 67

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SLIDE 100

Relative Precedence

[ab] relatively precedes [c] iff

(1) [ab] precedes [c] and (2) no [a] intervenes between [ab] and [c]

The second conjunct captures the “nearest-preceding” aspect of the Chumash description above. SiSlusisin ‘they (dual) are gone awry’ [Si] precedes [s] but [Si] does not relatively precede [s] Thus local blocking is achieved by not including (Si,s) in the grammar but including (St,s).

  • J. Heinz (100) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 65 / 67

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SLIDE 101

Learning Relativized Precedence Bigram Grammars

The learner simply records the relativized precedence bigram relations

  • bserved.

Precedence G =                                       Sample = { } The learner has already generalized: it accepts [SiS, Sin, Slun, Slis, sisisin] but not to words like [Sis, Silus].

  • J. Heinz (101) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 66 / 67

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SLIDE 102

Learning Relativized Precedence Bigram Grammars

The learner simply records the relativized precedence bigram relations

  • bserved.

Precedence G =                    (Si,S) (iS,l) (iS,u) (iS,s) (iS,i) (iS,n) (Sl,u) (Sl,s) (Sl,i) (Sl,n) (lu,s) (lu,i) (lu,n) (us,s) (us,i) (us,n) (si,s) (si,n) (is,i)                    Sample = { SiSlusisin } The learner has already generalized: it accepts [SiS, Sin, Slun, Slis, sisisin] but not to words like [Sis, Silus].

  • J. Heinz (102) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 66 / 67

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SLIDE 103

Learning Relativized Precedence Bigram Grammars

The learner simply records the relativized precedence bigram relations

  • bserved.

Precedence G =                    (Si,S) (iS,l) (iS,u) (iS,s) (iS,i) (iS,n) (Sl,u) (Sl,s) (Sl,i) (Sl,n) (lu,s) (lu,i) (lu,n) (us,s) (us,i) (us,n) (si,s) (si,n) (is,i)                    Sample = { SiSlusisin } The learner has already generalized: it accepts [SiS, Sin, Slun, Slis, sisisin] but not to words like [Sis, Silus].

  • J. Heinz (103) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 66 / 67

slide-104
SLIDE 104

Learning Relativized Precedence Bigram Grammars

The learner simply records the relativized precedence bigram relations

  • bserved.

Precedence G =                    (Si,S) (iS,l) (iS,u) (iS,s) (iS,i) (iS,n) (Sl,u) (Sl,s) (Sl,i) (Sl,n) (lu,s) (lu,i) (lu,n) (us,s) (us,i) (us,n) (si,s) (si,n) (is,i)                    Sample = { SiSlusisin } The learner has already generalized: it accepts [SiS, Sin, Slun, Slis, sisisin] but not to words like [Sis, Silus].

  • J. Heinz (104) (University of Delaware)

Learning Long Distance Phonotactics June 12, 2008 66 / 67

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SLIDE 105

Albright, Adam. 2006. Gradient Phonotactic effects: lexical? grammatical? both? neither? Talk handout from the 80th Annual LSA Meeting, Albuquerque, NM. Albright, Adam and Bruce Hayes. 2002. Modeling English past tense intuitions with minimal generalization. SIGPHON 6: Proceedings of the Sixth Meeting of the ACL Special Interest Group in Computational Phonology :58–69. Albright, Adam and Bruce Hayes. 2003a. Learning NonLocal Environments. Talk Handout of 77th Annual Meeting of LSA, Atlanta Georgia. Albright, Adam and Bruce Hayes. 2003b. Rules vs. Analogy in English Past Tenses: A Computational/Experimental Study. Cognition 90:119–161. Albro, Dan. 1998. Evaluation, implementation, and extension of Primitive Optimality Theory. Master’s thesis, University of California, Los Angeles. Albro, Dan. 2005. A Large-Scale, LPM-OT Analysis of Malagasy. Ph.D. thesis, University of California, Los Angeles. Alderete, John, Adrian Brasoveanua, Nazarre Merchant, Alan Prince, and Bruce Tesar.

  • J. Heinz (105) (University of Delaware)

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