NAME
README - [documentation] Introduction to WordNet::Similarity
SYNOPSIS
There are a number of documentation files covering different aspects of
WordNet::Similarity available:
* intro.pod Introduction to WordNet::Similarity (this document)
* install.pod How to install
* utils.pod How to use the utility programs in /utls
* modules.pod How the measure modules are designed
* developers.pod How to write your own measure of semantic relatedness
* config.pod How to set configuration options for the measures
You can use pod2html, pod2latex, pod2man, or pod2text to get this
documentation in a different format. See the man pages for pod2html,
etc. These translators should come with Perl, but you can also download
them from <
http://search.cpan.org>.
DESCRIPTION
This package consists of Perl modules along with supporting Perl
programs that implement the semantic relatedness measures described by
Leacock & Chodorow (1998), Jiang & Conrath (1997), Resnik (1995), Lin
(1998), Hirst & St-Onge (1998), Wu & Palmer (1994), the extended gloss
overlap measure by Banerjee and Pedersen (2002), and two measures based
on context vectors by Patwardhan (2003). The details of the vector
measure are described in the Master's thesis work of Patwardhan (2003)
at the University of Minnesota Duluth, and the vector_pairs measure is
derived from that.
The Perl modules are designed as objects with methods that take as input
two word senses. The semantic relatedness of these word senses is
returned by these methods. A quantitative measure of the degree to which
two word senses are related has wide ranging applications in numerous
areas, such as word sense disambiguation, information retrieval, etc.
For example, in order to determine which sense of a given word is being
used in a particular context, the sense having the highest relatedness
with its context word senses is most likely to be the sense being used.
Similarly, in information retrieval, retrieving documents containing
highly related concepts are more likely to have higher precision and
recall values.
A command line interface to these modules is also present in the
package. The simple, user-friendly interface returns the relatedness
measure of two given words. A number of switches and options have been
provided to modify the output and enhance it with trace information and
other useful output. Details of the usage are provided in other sections
of this README. Supporting utilities for generating information content
files from various corpora are also available in the package. The
information content files are required by three of the measures for
computing the relatedness of concepts.
The following sections describe the organization of this software
package and how to use it. A few typical examples are given to help
clearly understand the usage of the modules and the supporting
utilities.
SEMANTIC RELATEDNESS
We observe that humans find it extremely easy to say if two words are
related and if one word is more related to a given word than another.
For example, if we come across two words -- 'car' and 'bicycle', we know
they are related as both are means of transport. Also, we easily observe
that 'bicycle' is more related to 'car' than 'fork' is. But is there
some way to assign a quantitative value to this relatedness? Some ideas
have been put forth by researchers to quantify the concept of
relatedness of words, with encouraging results.
A number of different measures of relatedness have been implemented in
this software package. These include a simple edge counting approach and
a random method for measuring relatedness. The measures rely heavily on
the vast store of knowledge available in the online electronic
dictionary -- WordNet. So, we use a Perl interface for WordNet called
WordNet::QueryData to make it easier for us to access WordNet. The
modules in this package REQUIRE that the WordNet::QueryData module be
installed on the system before these modules are installed.
CONTENTS
The package contains the semantic relatedness modules, some support Perl
utilities and some sample configuration files, data files and programs.
Modules
All the modules that will be installed in the Perl system directory are
present in the '/lib' directory tree of the package. These include the
semantic relatedness modules -- jcn.pm, res.pm, lin.pm, lch.pm, hso.pm,
lesk.pm, vector.pm, vector_pairs.pm, wup.pm, path.pm and random.pm --
present in the /lib/WordNet/Similarity subdirectory and the supporting
modules get_wn_info.pm and string_compare.pm. There also exists a
WordNet/Similarity.pm module that currently serves as a base class for
all the relatedness modules and contains Perl documentation. All these
modules, once installed in the Perl system directory, can be directly
used by Perl programs.
Supporting Utilities
The '/utils' subdirectory of the package contains supporting Perl
programs. 'similarity.pl' is a command-line interface to the relatedness
modules. A number of Perl programs, that generate information content
files from various corpora, are provided. As part of the standard
install, these are also installed into the system directories, and can
be accessed from any working directory if the common system directories
(/usr/bin, /usr/local/bin, etc) are in your path.
Samples
If you downloaded this package as a tar-gzipped file from the web, you
will find a '/samples' subdirectory in the package. There is a separate
README in that directory. The directory contains sample configuration
files for the modules, sample programs showing usage of the modules and
sample data files (e.g., relation files).
REFERENCES
1 Wu Z. and Palmer M. 1994. Verb Semantics and Lexical Selection. In
Proceedings of the 32nd Annual Meeting of the Association for
Computational Linguistics. Las Cruces, New Mexico.
2 Resnik P. 1995. Using information content to evaluate semantic
similarity. In Proceedings of the 14th International Joint
Conference on Artificial Intelligence, pages 448-453. Montreal.
3 Jiang J. and Conrath D. 1997. Semantic similarity based on corpus
statistics and lexical taxonomy. In Proceedings of International
Conference on Research in Computational Linguistics. Taiwan.
4 Fellbaum C., editor. WordNet: An electronic lexical database. MIT
Press, 1998.
5 Leacock C. and Chodorow M. 1998. Combining local context and WordNet
similarity for word sense identification. In Fellbaum 1998, pp.
265-283.
6 Lin D. 1998. An information-theoretic definition of similarity. In
Proceedings of the 15th International Conference on Machine
Learning. Madison, WI.
7 Hirst G. and St-Onge D. 1998. Lexical Chains as representations of
context for the detection and correction of malapropisms. In
Fellbaum 1998, pp. 305-332.
8 Sch�tze H. 1998. Automatic Word Sense Discrimination. Computational
Linguistics, 24(1):97-123.
9 Resnik P. 1999. Semantic Similarity in a Taxonomy: An Information-
Based Measure and its Applications to Problems of Ambiguity in
Natural Language. Journal of Artificial Intelligence Research, 11,
95-130.
10 Budanitsky A. and Hirst G. 2001. Semantic distance in WordNet: An
experimental, application-oriented evaluation of five measures. In
Workshop on WordNet and Other Lexical Resources, Second meeting of
the North American Chapter of the Association for Computational
Linguistics. Pittsburgh, PA.
11 Banerjee S. and Pedersen T. 2002. An Adapted Lesk Algorithm for Word
Sense Disambiguation Using WordNet. In Proceeding of the Fourth
International Conference on Computational Linguistics and
Intelligent Text Processing (CICLING-02). Mexico City.
12 Patwardhan S., Banerjee S. and Pedersen T. 2002. Using Semantic
Relatedness for Word Sense Disambiguation. In Proceedings of the
Fourth International Conference on Intelligent Text Processing and
Computational Linguistics. Mexico City.
13 Banerjee S. and Pedersen T. 2003. Extended Gloss Overlaps as a
Measure of Semantic Relatedness. In the Proceedings of the
Eighteenth International Joint Conference on Artificial
Intelligence. Acapulco, Mexico.
14 Patwardhan S. and Pedersen T. 2006. Using WordNet-based Context
Vectors to Estimate the Semantic Relatedness of Concepts. In the
Proceedings of the EACL 2006 Workshop Making Sense of Sense -
Bringing Computational Linguistics and Psycholinguistics Together.
Trento, Italy.
15 Banerjee S. Adapting the Lesk algorithm for word sense
disambiguation to WordNet. Master Thesis, University of Minnesota,
Duluth, 2002.
16 Patwardhan S. Incorporating dictionary and corpus information into a
vector measure of semantic relatedness. Master Thesis, University of
Minnesota, Duluth, 2003.
SEE ALSO
intro.pod
Mailing list: <
http://groups.yahoo.com/group/wn-similarity>
Project Home page: <
http://wn-similarity.sourceforge.net>
ACKNOWLEDGEMENTS
We would like to thank the following for their support and contribution
towards the development of this package. We thank Jason Rennie for his
QueryData package, the WordNet guys at Princeton for WordNet, Resnik,
Hirst, St-Onge, Jiang, Conrath, Lin, Wu, Palmer, Leacock, and Chodorow
for their algorithms and work on the relatedness measures. We also thank
Bano (Satanjeev Banerjee) for his work on the extended gloss overlap
module. We are grateful to Wybo Wiersma for contributing his
optimizations to the GlossFinder code. We also appreciate the many
helpful suggestions and bug patches from Ben Haskell.
AUTHORS
Ted Pedersen, University of Minnesota Duluth
tpederse at d.umn.edu
Siddharth Patwardhan, University of Utah, Salt Lake City
sidd at cs.utah.edu
Satanjeev Banerjee, Carnegie Mellon University, Pittsburgh
banerjee+ at cs.cmu.edu
Jason Michelizzi
COPYRIGHT
Copyright (c) 2005-2008, Ted Pedersen, Siddharth Patwardhan, Satanjeev
Banerjee, and Jason Michelizzi
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no
Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
Note: a copy of the GNU Free Documentation License is available on the
web at <
http://www.gnu.org/copyleft/fdl.html> and is included in this
distribution as FDL.txt.