Dissertation - Michael Becker

CHAPTER 4LEXICAL TRENDS AS OPTIMALITY THEORETIC GRAMMARS4.1 IntroductionThe results presented in chapters 2 and 3 were used to motivate a framework, basedon Optimality Theory (Prince & Smolensky 1993/2004), that learns lexical trends andprojects them onto novel items.The mechanism for learning a lexical trend from anambient language relied on the Recursive Constraint Demotion algorithm (RCD, Tesar& Smolensky 1998, 2000; Tesar 1998; Prince 2002), augmented with a mechanism ofconstraint cloning (Pater 2006, 2008b).This chapter goes on to develop this version of OT in greater detail and in greatergenerality. It starts with a discussion of the cloning mechanism in §4.2, with a focus onthe question of identifying the constraint to clone. Then, the learning algorithm is fleshedout formally in §4.3. The learning algorithm assumes that when learning paradigms, thesurface form of the base of the paradigm is always taken to be its underlying form, andnon-surface-true underlying representations are limited to affixes only. This assumption isexplored and motivated in §4.4. The use of OT constraints to account for lexical trendsmakes predictions about the typology of lexical trends, and §4.5 explores this typology.Conclusions are offered in §4.6.4.2 Choosing the constraint to cloneThe cloning algorithm proposed here is designed to achieve two goals: (a) resolveinconsistent ranking arguments, allowing the learner to use RCD and find a grammar evenwhen faced with an inconsistent lexicon, and (b) learn a grammar that reflects statistical145