Ling 571 - Deep Processing Techniques for NLP
Winter 2016
Homework #9: Due March 15, 2016: 23:45


Goals

Through this assignment you will:

Background

Please review the class slides (esp. Class 16, #19) and readings in the textbook on pronominal anaphora resolution and especially the Hobbs algorithm (J&M, 2nd ed,p. 704-705).

Analyzing Coreference Resolution with the Hobbs Algorithm

The Hobbs algorithm takes as input a pronoun and a sequence of sentence parse trees in the context, and returns the proposed antecedent. The data file contains a list of pairs of sentences separated by blank lines. In each pair of the sentences, the second sentence has one or more pronouns to be resolved. Parse the sentences, almost all of which are drawn from the first homework assignment, using the same techniques as in HW#1 (or HW#5 if you want to handle number agreement).

For each pronoun, in each sentence pair, trace the Hobbs algorithm to identify its antecedent.

Specifically, you should:

"Implementation"

You should implement steps i-iii.b) using NLTK and a suitable parser. You may do steps A-D either: Steps E-F* should be done manually.

Note: Manual processing should be done on a copy of the output of automatic processing.

Programming

Create a program hw9_coref.{py|pl|etc} to implement the automatic processing components of the pronominal anaphora resolution process described above invoked as:
hw9_coref.{py|pl|etc} <input_grammar_filename> <test_sentence_filename> <output_filename>

where:

Files

The files for this assignment may be found on patas in /dropbox/15-16/571/hw9/.

Test, Example, and Resource Files

Submission Files

Handing in your work

All homework should be handed in using the class CollectIt.