Product-oriented vs. source-oriented generalizations

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Experimental evidence for productoriented generalizations

(or not)

Vsevolod Kapatsinski

Indiana University

Dept. of Linguistics

Cognitive Science Program

Speech Research Laboratory vkapatsi@indiana.edu

http://mypage.iu.edu/~vkapatsi/

Product-oriented vs. source-oriented generalizations

• Bybee (2001:126)

“Generative rules express source-oriented generalizations. That is, they act on a specific input to change it in well-defined ways into an output of a certain form. Many, if not all, schemas are productoriented rather than source-oriented. A productoriented schema generalizes over forms of a specific category, but does not specify how to derive that category from some other.”

Source oriented: k] sg

 t  i] pl

Productoriented: ‘plurals must end in t  i’

Present study

• Given an artificial lexicon and a particular training paradigm what generalizations do the learners extract?

The paradigm

(Bybee & Newman 1995)

The artificial languages

BLUE RED

{k;g}  {t  ;d  }i 100%

30

{t;d;p;b}

{t;d;p;b}

{t;d;p;b}i

{t;d;p;b}a

25%

8

75%

24

75%

24

25%

8

Two plural suffixes –i and -a

If –i attached to a velar ({k;g}), the velar changes to an alveopalatal

This is velar palatalization

Velar palatalization

The process:

• k  t  /_i

Productivity:

• p (k  t  i ) / ( p (k  t  i ) + p (k  ki ) )

Coding scheme:

BLUE – velar palatalization applies

RED – velar palatalization fails

Research question

• Does the productivity of velar palatalization differ in the BLUE language and the RED language?

• Depends on your model of grammar.

The possible grammars

BLUE RED

{k;g}  {t  ;d  }i

{t;d;p;b}  {t;d;p;b}i

{t;d;p;b}  {t;d;p;b}a

25%

8

75%

24

100%

30 /62

75%

24

25%

8

Triggers velar palatalization

Does not compete with anything

Non-competing rules

Equally supported in both languages

BLUE = RED

BLUE RED

{k;g}  {t  ;d  }i 100%

30

{t;d;p;b}  {t;d;p;b}i

{t;d;p;b}  {t;d;p;b}a

25%

8

75%

24

75%

24

25%

8 e.g., Hale and Reiss 2008, Plag 2003

Triggers velar palatalization

Simple positive product-

BLUE

BLUE = RED

RED

{k;g}  {t  ;d  }i 100%

30

{t;d;p;b}

{t;d;p;b}

{t;d;p;b}i

{t;d;p;b}a

25%

8

75%

24

75%

24

25%

8

Bybee & Slobin 1982, Bybee & Moder 1983, Bybee 2001

Triggers velar palatalization

Negative product-oriented

/ki/ less expected in the blue language

 its absence is less notable

generalizations

BLUE < RED

BLUE RED

{k;g}  {t  ;d  }i

*ki

{t;d;p;b}  {t;d;p;b}i

100%

30

0

Ci

{t;d;p;b}  {t;d;p;b}a

25%

8

38

75%

24

75%

24

54

25%

8

Triggers velar palatalization

Competes with

Competition stronger in red

Competing weighted rules

BLUE > RED

BLUE RED

{k;g}  {t  ;d  }i 100%

30

C

C

Ci

Ca

25%

8

75%

24

Iff the choice between the rules is stochastic.

75%

24

25%

8

Albright & Hayes 2003

Triggers velar palatalization

Conditional product-

More reliable in blue

oriented generalizations

BLUE > RED

BLUE RED

{k;g}  {t  ;d  } | i 30/38 30/54

{t;d;p;b}  {t;d;p;b} | i 8/38 24/54

{t;d;p;b}  {t;d;p;b} | a 1 1

Aslin et al. 1998

Result

BLUE RED

Results

100%

30 Non-competing rules

*

Simple positive product-oriented

Negative product-oriented

Competing weighted rules

Conditional product-oriented

BLUE RED

Individual subject data

C  Ci

{p;b;t;d}

C  Ca

{p;b;t;d}

Competing weighted rules

{k;g}  {t  ;d  }i

BLUE RED

25%

8

75%

24

100%

30

75%

24

25%

8

Albright & Hayes 2003

Results

***

Competing weighted rules

ANCOVA:

This correlation is significant

F(1,27)=14.23, p<.001

, while Language is not,

F(1,27)=.082, p>.5) .

The predicted explanatory variable accounts for all the variance in velar palatalization rate attributable to the artificial language

22

The competing rules look good.

Can we pit them against

(conditional) product-oriented generalizations directly?

Conditional product-oriented generalizations

{k;g}  {t  ;d  } | i

{t  ;d  }  {t  ;d  } | i

{t;d;p;b}  {t;d;p;b} | i

{t;d;p;b}  {t;d;p;b} | a

BLUE

Support vel.pal

8/38

1

RED

Support vel.pal

24/54

1

{k;g}  {t  ;d  }i

{t  ;d  }  {t  ;d  }i

C  Ci

C  Ca

Competing weighted rules

BLUE RED

Oppose vel.pal

75%

24

100%

30

Oppose vel.pal

25%

8

Competing weighted rules r(33) = -.49, p=.003

The addition of t   t  i hurts vel.pal

Competing weighted rules

(Conditional) product-oriented t(33)=2.88, p=.007

Something that looks productoriented but isn’t

BLUE RED

Result: All subjects attach

–i rather than –a to singulars ending in {t  ;d ʒ}

In the Blue Language even more than to singulars ending in {k;g}

H: Because both languages have plurals ending in {t  ;dʒ}i, not {t  ;dʒ}a.

A productoriented schema? ‘Plurals must end in {t  ;dʒ}i’.

Why not?

• If

– {t  ;dʒ}  {t  ;dʒ}i because of ‘Plurals must end in {t  ;dʒ}i’, and this is the schema that does

{k;g}  {t  ;dʒ}i,

• Then

– there should be a positive correlation between rate of {k;g}  {t  ;dʒ}i and rate of {t  ;dʒ} 

{t  ;dʒ}i

• But r=-.03, n.s.

It’s categorization of source forms.

Why more –i with {t  ;d ʒ

} than with {k;g}?

Subjects have a bias against stem changes.

The more a subject attaches –i to velars, the more s/he attaches it to alveopalatals.

Prior experimental evidence for productoriented generalizations

• Frequent output patterns get ‘overused’, being derived from inputs in ways that are not attested in the lexicon, e.g., [v  n] 

[v  ]

(Bybee & Moder, 1983)

.

(Also see Köpcke 1988, Lobben 1991, Wang and Derwing 1994,

Albright and Hayes 2003)

• H: because the subjects have generalized

‘past tense forms must end in [  ]’

An alternative interpretation

• H’: The production of an output primes sublexical chunks occurring in that output.

• Lobben (1991)

– “the plurals [that don’t obey the rules but all end in ooCii] are appearing concentrated and subsequently… and… this is a typical characteristic of all other plural patterns’ (Lobben 1991:173),

– ‘[In this example] the second syllable of the singular is left out in the plural form, which never happens with real nouns… The surrounding… plurals, two preceding and seven following… are trisyllabic [in accordance with sourceoriented rules]. This… provides an explanation as to why the plural [in this example], which, if produced according to the rule… , would have four syllables, is made to have three syllables in a very unorthodox way’ (Lobben 1991:182)

• Presupposition: the output is more salient than the input  chunks from the output are more likely to persist and be reused than chunks from the input

Are products more salient than sources?

• During training, subjects repeated the word pairs they heard.

• Subjects have a bias against stem changes

 If the product is more salient, they should tend to erroneously make the shape of the singular fit the shape of the plural.

 If the source is more salient, the plural should fit the singular.

Products are more salient

χ 2 =28.9, p<.0001

t   t  i k k  t  i repeated as

 ki

Summary

In this AGL paradigm (Bybee & Newman 1995),

• Learners extract competing rules

• The outcome of competition is influenced by reliability or type frequency (Albright and Hayes 2003, Pierrehumbert

2006)

• The choice between rules is stochastic

• No evidence for product-oriented generalizations.

Future work: Role of the training paradigm.

35

Summary

Product forms are more salient than source forms. Thus creating a product may prime chunks and patterns that occur in that product for immediate reuse.

This product priming may result in ‘overuse’ of frequent product patterns

(found by Bybee & Moder 1983, Koepcke 1988,

Lobben 1991, Wang & Derwing 1994, Albright & Hayes, 2003).

If long-lasting, it may also result in the emergence of product-oriented schemas over time.

36

References

Albright, A., and B. Hayes. 2003. Rules vs. analogy in English past tenses: A computational/experimental study. Cognition , 90, 119-61.

Aslin, R. N., J. R. Saffran, & E. L. Newport. 1998. Computation of conditional probability statistics by 8-month-old infants. Psychological Science , 9, 321-4.

Bybee, J. L. 2001. Phonology and language use . CUP.

Bybee, J. L., & C. L. Moder. 1983. Morphological classes as natural categories. Language ,

59, 251-70.

Bybee, J. L., & J. E. Newman. 1995. Are stem changes as natural as affixes? Linguistics , 33,

633-54.

Bybee, J. L., & D. I. Slobin. 1982. Rules and schemas in the development and use of the

English past. Language 58: 265-89.

Hale, M., & C. Reiss. 2008. The phonological enterprise.

OUP.

Köpcke, K.-M. 1988. Schemas in German plural formation.

Lingua , 74, 303-35.

Lobben, M. 1991. Pluralization of Hausa nouns, viewed from psycholinguistic experiments and child language data . M.Phil Thesis, University of Oslo.

Pierrehumbert, J. B. 2006. The statistical basis of an unnatural alternation. In Laboratory

Phonology 8 , 81-107. Mouton de Gruyter.

Plag, I. 1999. Word formation in English . Mouton de Gruyter.

Wang, H. S., & B. L. Derwing. 1994. Some vowel schemas in three English morphological classes: Experimental evidence. In M. Y. Chen & O. C. L. Tseng, eds. In honor of

Professor William S.-Y. Wang: Interdisciplinary studies on language and language change , 561-75. Taipei: Pyramid Press.

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