The Weekly Newsletter of MIT Linguistics

Phonology Circle 3/29: Youngah Do

Phonology Circle this week features a CLS practice talk by Youngah Do

Speaker: Youngah Do
Title: Why do Korean children learn some alternations before others?
Time: Monday 3/29, 5pm
Location: 32-D831

Korean verbs show numerous alternations. Children acquiring Korean are reported to go through a stage in which they produce some alternations but not others (Do, to appear). The current simulation uses the MaxEnt Grammar Tool (Hayes, 2006) to explore why some alternations are acquired late. It shows that the frequency of different alternations in Korean can give rise to the attested intermediate stage, without assuming intrinsic bias.

The learner is assumed to have a set of constraints, and weights them according to the frequency of violations in the data. Following Hayes (2004), learning is simulated in two stages; phonotactic and morphological learning. The phonotactic learning stage models the fact that even prior to learning morphology, learners master phonotactic distributions. Once morphological relations are discovered, learners may wish to avoid alternations. I model this with output-output faithfulness constraints (OO-F), demanding faithful to a base form.

After two-stage learning, the learner was able to demote all OO-F to master all alternations. The interest of the current study, though, is to simulate a stage in which learning is incomplete. I simulated this by controlling how freely the model can change the weights of OO-F. By decreasing sigma, the learner is biased to leave the weights closer to their high initial weights.

The grammar trained purely by the frequency of different alternations perfectly predicts the child forms. Therefore, this study demonstrates that even without intrinsic bias, the statistics of Korean gives rise to the attested intermediate learning stage.

Upcoming talks:

  • Apr 5 Mafuyu Kitahara (Waseda University)
  • Apr 12 Haruka Fukazawa (Keio University)
  • Apr 26 Jae Yung Song (Brown University)
  • May 3 Igor Yanovich and Donca Steriade
  • May 10 Donca Steriade
  • May 17 Ari Goldberg (Tufts)

Access real-time updates, on-line:

via the web (click ‘agenda’ to see the schedule as a list), or through iCal