Tag Archives: Phonology

Computational Phonology (Guest Speaker Ewan Dunbar, 2/5/13)

Ewan Dunbar, a grad student at UMD, spoke to us about fundamental computational properties of our phonology processors. He focused on the way stress patterns work across different languages, and related them to function machines and the Chomsky hierarchy.

Background Reading
He asked that we read Sentence and Word Complexity and Computational Phonology Part I. He also suggested reading Computational Phonology Part II and Phonological Rules too. We have a summary sheet of all the readings in the Google Drive Resources collection.

Summary
Ewan first showed us different stress patterns in various languages and how they were all variations on alternating stress (more detail available here, here, and here). He then showed us a couple Finite State Machines (FSMs), and showed that stress patterns could be identified with FSMs, before generalizing this to all phonological patterns. But FSMs are very limited (see Chomsky Hierarchy lecture) – for example, they can’t recognize the set of palindromes (prove via the pumping lemma). Syntactic structure is an example of pattern class that can’t be recognized by FSMs. This leads us to believe that syntax and phonology are two separate cognitive systems, because of their computationally different complexities.