優選理論
優選理論（，優化理論、最優性理論、最適性理論，簡稱：OT），是一種語言學模型，該理論認為語言表面可見的形式源自數個互相衝突的約制(constraints)之間的相互作用。優選理論不同於其他音韻分析方法，像是自動段音韻學（）及線性音韻學（）等理論通常以規則(rules)描述而非限制(constraints)。優選理論將語法規則(grammars)模型化為一系統，此系統提供從輸入到輸出的映射(mapping)；基本上，輸入被視為底层形式（），而輸出則是表层形式（surface representation）。
在語言學中，優選理論的起源於1991年"艾倫·普林斯"（Alan Prince）及"保羅·斯摩棱斯基"（Paul Smolensky）的談話，[1]後來在由同作者於1993年的文章中發表出來。[2]
理論
優選理論有三個基本構成要件：
- GEN 選擇一個輸入(input)，並產生一系列可能的輸出(output)，或稱為候選項目，
- CON 提供準則，此準則以數個嚴密有序的可"違反約制"(violable constraint)之形式表示，用以決定候選項目，然後
- EVAL 根據這些限制選出的最佳候選項目，此項目即為輸出(output)。
優選理論假定這些構成要件具有普遍性。語法中的差異反映出CON組中各項具普遍性的約制有著不同的優先順序。語言習得的部分進程因此可被描述為調整這些約制之優先順序的過程。
優選理論最初於1993年由語言學家艾倫·普林斯（）和保羅·斯莫林斯基（）所提出的，後來由艾倫·普林斯和約翰·J·麥卡錫（）接續發展此理論。雖然優選理論獲得的許多關注一直與其在音位學中的運用有關，優選理論最早也是被應用於此領域，但是該理論也適用於語言學的其他子領域(例如語法學和語義學)。
優選理論如同其他生成語法的各種理論，著重於普遍原則（）、語言類型學及語言習得方面的探索。
優選理論亦植基於人工神經網路研究，此理論被提出，有幾分是為了要取代協和語法（）的聯結主義理論，協和語法是於1990年由Géraldine Legendre、宮田義郎(Yoshiro Miyata)與保罗·斯摩棱斯基發展出來的理論。[3]一些優選理論的變異理論裡存在偏重類聯結主義的約制，且在近期的研究裡持續被採用。
輸入及GEN:候選集合
優選理論假設沒有任何特定語言輸入上的約制。這被稱為"基礎的寬容"(richness of the base)。每個語法都可以處理每一個可能的輸入。一種語言的語法（其約制排名）決定了哪些未定的候選項目將被 EVAL 評估為優選項目。
CON：約制集
在優選理論中，每個約束都是普遍的。CON 在每種語言中都是一樣等位的。有兩種基本類型的約制。
馬秋武(2008)的整理
後SPE論
- 非線遞音韻學
- 音韻音段的內部結構(PSIS)與音韻特徵理論(PFT)
- 音節(syllable)地位的確立
- 韻律音韻(PrsP)和語調音韻(IntP)
- 音韻表層制約(SC)
理論
- 生成器
- 評估器
- 制約條件的等級排列
- 制約條件
忠實性制約
McCarthy & Prince (1995) propose three basic families of faithfulness constraints:
- Max-IO/BR(反刪-輸入輸出/基數重複數) prohibits deletion (from "maximal").
- Dep-IO(反插-輸入輸出/基數重複數)prohibits epenthesis (from "dependent").
- Ident(F) (特徵忠實性)prohibits alteration to the value of feature F (from "identical").
McCarthy & Prince (1995) also propose:
- I-Contig(輸入-連續性), violated when a word- or morpheme-internal segment is deleted (from "input-contiguity");
- O-Contig(輸出-連續性), violated when a segment is inserted word- or morpheme-internally (from "output-contiguity");
- Linearity(線性/反分解), violated when the order of some segments is changed (i.e. prohibits metathesis);
- Uniformity(均勻性/反融合), violated when two or more segments are realized as one (i.e. prohibits fusion); and
- Integrity(完整性/反隔離), violated when a segment is realized as multiple segments (i.e. prohibits unpacking or vowel breaking—opposite of Uniformity).
標記性制約
Markedness constraints introduced by Prince & Smolensky (1993) include:
| Name | Statement | Other names |
|---|---|---|
| Nuc | Syllables must have nuclei(有韻核). | |
| −Coda | Syllables must have no codas(無韻尾). | NoCoda(無韻尾) |
| Ons | Syllables must have onsets(音節有首音). | Onset(有首音) |
| HarNuc | A nuclear segment must be more sonorous(響度高)than another (from "harmonic nucleus"響韻核). | HarmonicNucleus(響韻核) |
| *Comp | A syllable must be V, CV or VC.(單純) | NotComplex(不複雜) |
| CodaCond | Coda consonants cannot have place features that are not shared by an onset consonant.(韻尾輔音部位同於起始輔音final/codaC=initial/onsC) | CodaCondition(韻尾條件) |
| NonFin | A word-final syllable (or foot) must not bear stress(末音節無重音*StressFinS). | NonFinality(末音節無重音) |
| FtBin | A foot(音步) must be two syllables (or moras).(音步雙莫拉F2M) | FootBinarity(音步雙莫拉) |
| Pk-Prom | Light syllables(輕音節) must not be stressed.(輕音節無重音*StressLitS) | PeakProminence(輕音節無重音) |
| WSP | Heavy syllables must be stressed (from "weight-to-stress principle"重音節有重音StressHavS). | Weight-to-Stress(重音節有重音) |
優選論的發展和修正
制約條件合取
能較好解釋WOW、對分析因元音和諧、音段中和、強制性非同值原則(OCP無雙原則)變化，還有推導環境效應、祖父效應、鏈移現象等連續推導引起的音系晦暗現象很有幫助，至少提供了新的解決思路。 (複合體制約條件的排列規則限制了OT制約條件的階乘類型factorial type)
重複和共謀問題(repulication & conspiracy)
OT的並行處理(parallelism)模式通過制約條件(如格雷斯曼定律、顎化、音叢減少)交互作用(alternation)能較SPE更好的解決重複問題(包括構詞重複、超音段重複等)。
音系晦暗問題(opacity)
由於OT對音系晦暗現象的無奈，於是產生了推導性OT模式「有限和諧序列論」、分層優選論、對應理論、共感論(Sympathy和應論)、還有比較標記理論以及優選論候選項鏈式理論。
註釋
- "Optimality". Proceedings of the talk given at Arizona Phonology Conference, University of Arizona, Tucson, AZ.
- Prince, Alan, and Smolensky, Paul (1993) "Optimality Theory: Constraint interaction in generative grammar." Technical Report CU-CS-696-93, Department of Computer Science, University of Colorado at Boulder.
- Paul Smolensky; Geraldine Legendre,"The Harmonic Mind: From Neural Computation to Optimality-theoretic Grammar Cognitive Architecture",A Bradford Book; Reprint edition (January 21, 2011). ISBN 978-0262516198
參考文獻
- Brasoveanu, Adrian, and Alan Prince (2005). Ranking & Necessity. ROA-794.
- Chomsky (1995). The Minimalist Program. Cambridge, MA: The MIT Press.
- Dresher, Bezalel Elan (1996): The Rise of Optimality Theory in First Century Palestine 页面存档备份，存于. GLOT International 2, 1/2, January/February 1996, page 8 (a humorous introduction for novices)
- Hale, Mark, and Charles Reiss (2008). The Phonological Enterprise. Oxford University Press.
- Halle, Morris (1995). Feature Geometry and Feature Spreading. Linguistic Inquiry 26, 1-46.
- Heinz, Jeffrey, Greg Kobele, and Jason Riggle (2009). Evaluating the Complexity of Optimality Theory 页面存档备份，存于. Linguistic Inquiry 40, 277-288.
- Idsardi, William J. (2006). A Simple Proof that Optimality Theory is Computationally Intractable 页面存档备份，存于. Linguistic Inquiry 37:271-275.
- Idsardi, William J. (2000). Clarifying opacity. The Linguistic Review 17:377-50.
- Kager, René (1999). Optimality Theory. Cambridge: Cambridge University Press.
- Kornai, Andras (2006). Is OT NP-hard?. ROA-838.
- Legendre, Géraldine, Jane Grimshaw and Sten Vikner. (2001). Optimality-theoretic syntax. MIT Press.
- McCarthy, John (2007). Hidden Generalizations: Phonological Opacity in Optimality Theory. London: Equinox.
- McCarthy, John (2001). A Thematic Guide to Optimality Theory. Cambridge: Cambridge University Press.
- McCarthy, John and Alan Prince (1993): Prosodic Morphology: Constraint Interaction and Satisfaction 页面存档备份，存于. Rutgers University Center for Cognitive Science Technical Report 3.
- McCarthy, John and Alan Prince (1994): The Emergence of the Unmarked: Optimality in Prosodic Morphology 页面存档备份，存于. Proceedings of NELS.
- McCarthy, John J. & Alan Prince. (1995). Faithfulness and reduplicative identity. In J. Beckman, L. W. Dickey, & S. Urbanczyk (Eds.), University of Massachusetts occasional papers in linguistics (Vol. 18, pp. 249–384). Amherst, MA: GLSA Publications.
- Moreton, Elliott (2004): Non-computable Functions in Optimality Theory. Ms. from 1999, published 2004 in John J. McCarthy (ed.), Optimality Theory in Phonology.
- Prince, Alan (2007). The Pursuit of Theory. In Paul de Lacy, ed., Cambridge Handbook of Phonology.
- Prince, Alan (2002). Entailed Ranking Arguments 页面存档备份，存于. ROA-500.
- Prince, Alan (2002). Arguing Optimality. In Coetzee, Andries, Angela Carpenter and Paul de Lacy (eds). Papers in Optimality Theory II. GLSA, UMass. Amherst. ROA-536.
- Prince, Alan and Paul Smolensky. (1993/2002/2004): Optimality Theory: Constraint Interaction in Generative Grammar. Blackwell Publishers (2004) 页面存档备份，存于(2002). Technical Report, Rutgers University Center for Cognitive Science and Computer Science Department, University of Colorado at Boulder (1993).
- Trommer, Jochen. (2001). Distributed Optimality 页面存档备份，存于. PhD dissertation, Universität Potsdam.
- Wolf, Matthew. (2008). Optimal Interleaving: Serial Phonology-Morphology Interaction in a Constraint-Based Model. PhD dissertation, University of Massachusetts. ROA-996.