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Optimality Theory Presented by Ashour Abdulaziz, Eric Dodson, Jessica Hanson, and Teresa Li.

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Presentation on theme: "Optimality Theory Presented by Ashour Abdulaziz, Eric Dodson, Jessica Hanson, and Teresa Li."— Presentation transcript:

1 Optimality Theory Presented by Ashour Abdulaziz, Eric Dodson, Jessica Hanson, and Teresa Li

2 Overview Introduction How to interpret OT Historical Development Theory Application Pros and Cons

3 Optimality Theory Central Idea: Surface Forms of language reflect resolutions of conflicts between competing demands or constraints. Language is a system of conflicting forces. The scope of OT is to explain a wide range of linguistic phenomena (including syntax)

4 Constraints Constraints are: Universal Ranked Violable In Conflict

5 In other words… Constraints are universal, but cross- linguistic differences are accounted for by differences in ranking. All surface forms violate at least some constraints. The optimal surface form will have the least serious violations of the ranked set of constraints for a language.

6 What's for lunch? Jessica doesn't want to go far Eric wants a place that has a lunch special Ashour wants a place that has soup Teresa is trying to be vegan Options: Chit-chat, Cafe Yumm, Park Cafe, Kenny & Zuke's

7 What's for lunch? /input/*Far awaySoupVegan Options *Lunch Special Chit-Chat Cafe Yumm Park Cafe Kenny & Zuke's

8 What's for lunch? /input/*Far awaySoupVegan Options *Lunch Special Chit-Chat*!** Cafe Yumm * Park Cafe*! Kenny & Zuke's *!

9 This is for lunch. /input/*Far awaySoupVegan Options *Lunch Special Chit-Chat*!** Cafe Yumm * Park Cafe*! Kenny & Zuke's *!

10 Optimality Theory - History It is a linguistic model proposing that the observed forms of language arise from the interaction between conflicting constraints. OT models grammars as systems that provide mappings from inputs to outputs; the inputs are conceived of as underlying representations and the outputs as their surface realizations

11 Pre-OT History Theoretical problem with generative phonology: Conspiracies Kisseberth (1970) Basic example: o A->B /X_Y o A->C /X_Y o A-> /X_Y The rules "conspire" against the form XAY Generative approaches have no explanation

12 Optimality Theory - History Prince and Smolensky (1993) introduced the Optimality Theory (OT), as a framework for Linguistic analysis, Kager (1999) gave an introduction to the theory. The theory was later expanded by Prince and John McCarthy in (2001) Optimality theory is usually considered a development of generative grammar.

13 The fundamentals of OT How OT addresses the following questions:- (1) How are the constraints on the output of the grammar satisfied? What is the relationship between constraints on output structures and the operations that transform input into outputs? How are the triggering and blocking effects accounted for? (2) What is the relationship between the universal and the language particular? How can constraints differ in their activity from language to language?

14 Constraints Constraints are: Universal Ranked Violable In Conflict

15 Identifying Constraints Little agreement on what constraints exist Some disagreements (or flexibility) in how to propose a new constraint Language Typology Phonetic motivation

16 Markedness Markedness: enforce well-formedness of the output Unmarked: "preferred" Marked: "avoided" "Fights" against input that is marked Example: *Voiced Word-Final Obstruent Word-final obstruents must not be voiced.

17 Faithfulness Faithfulness: constraints enforce similarity between input and output Fights against change Example: Ident-IO(Voice) Segments in the output have the same voicing as those in the input

18 Functions Gen (Generator) Eval (Evaluator

19 Gen Underlying forms are input for gen Gen creates (possibly infinite) list of candidates /dogz/ dogztogz dogsgogz doksdogəz dokzdogəs do!sdogədog dugz...

20 Eval Applies ranking to candidate list Selects most harmonic candidate

21 An example analysis [d ɑ g][d ɑ gz] [kæt] [kæts] Assume plural morpheme is /z/ Explain variation between [z] and [s]

22 An example analysis Identify constraints Propose some candidates Propose a ranking Show alternate ranking

23 Proposed Constraints Agree-Voice - "Obstruent voicing agreement" Markedness constraint: contiguous obstruents must agree in voicing Ident-IO (Voice) - "Voicing Faithfulness" Faithfulness constraint: output segment voicing must be the same as input *Voiced Word-Final Obstruent - "No word-final voicing" Markedness constraint: word-final obstruents must not be voiced.

24 TPR Demo Input: /kæ t - z/ Find the optimal candidate given: 1. Agree-Voice 2. Ident-IO (Voice) 3. *Voiced Word-Final

25 Demo - Tableau

26 TPR Demo - Wrong Ranking What happens with the wrong ranking? Input: /kæ t - z/ Wrong ranking: 1. Ident-IO (Voice) 2. Agree-Voice 3. *Voiced Word-Final

27 Demo - Tableau Follow-up: What about the candidate [ka ʔ z]?

28 Pros of OT Expands to other areas of linguistics Unites different processes that are for the same purposes(conspiracy) o A->B /X_Y A->C /X_Y A->O /X_Y Eliminates derivation

29 Criticism of OT Existence of constraint not easily defined Ambiguity in how constraints are created Opacity difficult to explain "Too many solutions" problem o Reverse of conspiracy problem

30 Conclusion How to interpret a Tableaux History and Reasons for Development Theory Application Pros and Cons

31 Further Resources Kager, Rene (1999). Optimality Theory. Cambridge, UK: Cambridge University Press. OT Archive at Rutgers: http://roa.rutgers.edu/ http://roa.rutgers.edu/

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