The Weekly Newsletter of MIT Linguistics

ESSL/Language Acquisition Lab 9/21: Michael Clauss

Speaker: Michael Clauss (UMass)
Title: Classifying Adjectives without Semantic Information (joint work with Jeremy Hartman)
Time: 5-6:30pm
Place: 32D-461

The problem of children’s acquisition of “Tough” constructions in English has a long history. It has often been found that children commonly interpret the subjects of “Tough” sentences as the subjects of the embedded clauses rather than the objects, analogous to Control adjectives like “eager”. Numerous studies have shown this phenomenon (Chomsky 1969, Solan 1978, Anderson 2005). Recent work by Becker (2014) suggests that children are better than previously claimed, and can use semantic cues (namely subject animacy) to give the correct parse to sentences of this form, based on novel word learning experiments.

  • The teacher is ADJ to draw → The teacher1 is ADJ [PRO1 to draw]
  • The apple is ADJ to draw → The apple1 is ADJ [PROar b to draw (e)1]

The present work seeks to expand the picture developed by this recent work by examining what syntactic cues children (and adults) may use to parse potentially ambiguous strings with novel adjectives, particularly in environments with as little semantic content as possible. To answer this, we start with the observation that Tough and Control adjectives appear in a different range of syntactic frames. Thus, a novel adjective may be ambiguous between Tough and Control interpretations in some syntactic frames, but unambiguously Tough or Control if it is heard in others.

a John is daxy to see (ambiguous)
b It’s daxy to see John (tough only)
c John is daxy to see Bill (Control only)
d John is daxy to look at (tough only)

In our experiment, participants were taught a novel adjective in one of the frames in (a-d), and then tested by being asked questions about a series of pictures using the ambiguous frame (which one is daxy to [verb]). We found that children, aged 4-6, consistently skew toward Control readings no matter which frame was used in training. For adults, however, we found that training condition had a strong effect on performance on the test; adults were at chance responding when trained on the ambiguous condition a, but tended to give the expected answers on the other conditions. The different performance of children and adults adds support to the notion that, for children, semantic information is crucial to choose between the two adjective types, while for adults syntax does most of the work.

However, we also find that the Tough construction is still difficult to learn from syntax for adults: adults are less likely to give target responses in the conditions which should train for Tough syntax than for the condition that trains for Control. We also argue that this shows that there is some general bias towards Control-type interpretations for both children and adults which interacts with cues that signify Tough constructions. We discuss further paths to piecing together all the cues which might signify that a word is of either of these types.