PS: Introduction to Psycholinguistics
Winter Term 2005/06
Instructor: Daniel Wiechmann
Office hours: Mon 2-3 pm
Email: daniel.wiechmann@uni-jena.de
Phone: 03641-944534
Web: www.daniel-wiechmann.net
Session 5:
Understanding the structure of syntax
 Task: Parsing

Assign syntactic structure to incoming string of
words
Peter gave Mary the book
 N V N Det N
 S[NP[N] VP[V NP[N] NP[Det N]]]

Session 5:
Understanding the structure of syntax
 How does parsing operate?
 Why are some sentences more difficult to
parse than others?
 What happens to the syntactic representation
after parsing?
 How many stages of parsing are there?
Session 5:
Understanding the structure of syntax
 What happens if there is a choice of possible
structures at any point?
 At what stage is non-structural information
information used?
 Is there an enclosed (autonomous) syntactic
processor (module)?
Session 5:
Understanding the structure of syntax
 Assumptions:


Our knowledge of Grammar (and, therefore,
phrase structure) provides us with “templates”
for sentence structure
As we hear sentences, we assign incoming words
to phrases and phrases to nodes in these
templates
Session 5:
Understanding the structure of syntax
 Psycholingists usually represent the parsing
process as the on-line construction of PStrees



S -> NP + VP
NP -> (Det) + N
VP -> V + (NP)
Session 5:
Understanding the structure of syntax
 Early ideas about parsing (Fodor, Bever, and
Garrett, 1974)




First, we identify words on the basis of perceptual data
Recognition and lexical access give access to syntactic
category of a given word
We then use this information to build up a parse tree for
each clause
Finally we use parse tree to generate semantic
representaion
Session 5:
Understanding the structure of syntax
 Incremental parsing:

Language processor operates incrementally, i.e.
it rapidly constructs a syntactic analysis for a
sentence fragment, assigns it a semantic
interpretation, and relates this interpretation to
world knowledge
Session 5:
Understanding the structure of syntax
 Standing syntactic ambiguity


I saw the Alps flying to Romania
Peter said that Mary finished it yesterday
Session 5:
Understanding the structure of syntax
 Local syntactic ambiguity



The log floated past the bridge sank
The old man the boats
Since Jay always jogs a mile seems like a very
short distance to him
Session 5:
Understanding the structure of syntax
 Kimball (1973)

Structures are built guided by rules that are based
on that are based on psychological constraints
such as minimizing memory load
Session 5:
Understanding the structure of syntax
 Kimball (1973): Seven principles
Top-down-parsing (predict constituents)
 Right association
 New nodes
 Two nodes
 Closure
 Fixed structure
 Processing

Session 5:
Understanding the structure of syntax
 The sausage machine (Frazier and Fodor
1978)

Two-stage model
 Preliminary phrase packager (PPP)
 Sentence structure supervisor (SSS)
later became the garden path model (Frazier 1987)
 Minimal attachment

 Late closure
Session 5:
Understanding the structure of syntax
 Garden Path model:

Minimal attachment


Interpret sentences as having the simplest possible
sturcture
Late closure

Interpret incoming word as part of the node under
current construction
 Peter found the book in library.
 Peter found the book was the best book he ever read
Session 5:
Understanding the structure of syntax
 Constraint-based models of parsing



Processor uses multiple sources of information
(syntactic, semantic, frequency-based)
Construction that is most strongly supported is
most activated (and is usually the only to reach
the level of consciousness)
Garden paths occur when the correct analysis
receives little activation

(„The old man the boat“)