Word sense disambiguation and information retrieval

It has often been thought that word sense ambiguity is a cause of poor performance in Information Retrieval (IR) systems. The belief is that if ambiguous words can be correctly disambiguated, IR performance will increase. However, recent research into the application of a word sense disambiguator to an IR system failed to show any performance increase. From these results it has become clear that more basic research is needed to investigate the relationship between sense ambiguity, disambiguation, and IR. Using a technique that introduces additional sense ambiguity into a collection, this paper presents research that goes beyond previous work in this field to reveal the influence that ambiguity and disambiguation have on a probabilistic IR system. We conclude that word sense ambiguity is only problematic to an IR system when it is retrieving from very short queries. In addition we argue that if a word sense disambiguator is to be of any use to an IR system, the disambiguator must be able to resolve word senses to a high degree of accuracy

Word sense disambiguation and information retrieval

It has often been thought that word sense ambiguity is a cause of poor performance in Information Retrieval (IR) systems. The belief is that if ambiguous words can be correctly disambiguated, IR performance will increase. However, recent research into the application of a word sense disambiguator to an IR system failed to show any performance increase. From these results it has become clear that more basic research is needed to investigate the relationship between sense ambiguity, disambiguation, and IR. Using a technique that introduces additional sense ambiguity into a collection, this paper presents research that goes beyond previous work in this field to reveal the influence that ambiguity and disambiguation have on a probabilistic IR system. We conclude that word sense ambiguity is only problematic to an IR system when it is retrieving from very short queries. In addition we argue that if a word sense disambiguator is to be of any use to an IR system, the disambiguator must be able to resolve word senses to a high degree of accuracy

Word sense disambiguation and information retrieval

Starting with a review of previous research that attempted to improve the representation of documents in IR systems, this research is reassessed in the light of word sense ambiguity. It will be shown that a number of the attempts' successes or failures were due to the noticing or ignoring of ambiguity. In the review of disambiguation research, many varied techniques for performing automatic disambiguities are introduced. Research on the disambiguating abilities of people is presented also. It has been found that people are inconsistent when asked to disambiguate words and this causes problems when testing the output of an automatic disambiguator. The first of two sets of experiments to investigate the relationship between ambiguity, disambiguation, and IR, involves a technique where ambiguity and disambiguation can be simulated in a document collection. The results of these experiments lead to the conclusions that query size plays an important role in the relationship between ambiguity and IR. Retrievals based on very small queries suffer particularly from ambiguity and benefit most from disambiguation. Other queries, however, contain a sufficient number of words to provide a form of context that implicitly resolves the query word's ambiguities. In general, ambiguity is found to be not as great a problem to IR systems as might have been thought and the errors made by a disambiguator can be more of a problem than the ambiguity it is trying to resolve. In the complementary second set of experiments, a disambiguator is built and tested, it is applied to a document test collection, and an IR system is adjusted to accommodate the sense information in the collection. The conclusions of these experiments are found to broadly confirm those of the previous set

Formal models, usability and related work in IR (editorial for special edition)

The Glasgow IR group has carried out both theoretical and empirical work, aimed at giving end users efficient and effective access to large collections of multimedia data

Similarity of Semantic Relations

There are at least two kinds of similarity. Relational similarity is correspondence between relations, in contrast with attributional similarity, which is correspondence between attributes. When two words have a high degree of attributional similarity, we call them synonyms. When two pairs of words have a high degree of relational similarity, we say that their relations are analogous. For example, the word pair mason:stone is analogous to the pair carpenter:wood. This paper introduces Latent Relational Analysis (LRA), a method for measuring relational similarity. LRA has potential applications in many areas, including information extraction, word sense disambiguation, and information retrieval. Recently the Vector Space Model (VSM) of information retrieval has been adapted to measuring relational similarity, achieving a score of 47% on a collection of 374 college-level multiple-choice word analogy questions. In the VSM approach, the relation between a pair of words is characterized by a vector of frequencies of predefined patterns in a large corpus. LRA extends the VSM approach in three ways: (1) the patterns are derived automatically from the corpus, (2) the Singular Value Decomposition (SVD) is used to smooth the frequency data, and (3) automatically generated synonyms are used to explore variations of the word pairs. LRA achieves 56% on the 374 analogy questions, statistically equivalent to the average human score of 57%. On the related problem of classifying semantic relations, LRA achieves similar gains over the VSM

Retrieving with good sense

Although always present in text, word sense ambiguity only recently became regarded as a problem to information retrieval which was potentially solvable. The growth of interest in word senses resulted from new directions taken in disambiguation research. This paper first outlines this research and surveys the resulting efforts in information retrieval. Although the majority of attempts to improve retrieval effectiveness were unsuccessful, much was learnt from the research. Most notably a notion of under what circumstance disambiguation may prove of use to retrieval

The Reuters collection

This short paper presents the little known Reuters 22,173 test collection, which is significantly larger than most traditional test collections. In addition, Reuters has none of the recall calculation problems normally associated with some of the larger test collections now available. This paper explains the method (derived from Lewis [Lewis 91]) used to perform retrieval experiments on the Reuters collection. Then, to illustrate the use of Reuters, some simple retrieval experiments are also presented that compare the performance of stemming algorithms

A Topic-Sensitive Model for Salient Entity Linking

Abstract. In recent years, the amount of entities in large knowledge bases available on the Web has been increasing rapidly. Such entities can be used to bridge textual data with knowledge bases and thus help with many tasks, such as text understanding, word sense disambiguation and information retrieval. The key issue is to link the entity mentions in documents with the corresponding entities in knowledge bases, referred to as entity linking. In addition, for many entity-centric applications, entity salience for a document has become a very important factor. This raises an impending need to identify a set of salient entities that are central to the input document. In this paper, we introduce a new task of salient entity linking and propose a graph-based disambiguation solution, which integrates several features, especially a topic-sensitive model based on Wikipedia categories. Experimental results show that our method significantly outperforms the state-of-the-art entity linking methods in terms of precision, recall and F-measure

An Application of Word Sense Disambiguation to Information Retrieval

The problems of word sense disambiguation and document indexing for information retrieval have been extensively studied. It has been observed that indexing using disambiguated meanings, rather than word stems, should improve information retrieval results. We present a new corpus-based algorithm for performing word sense disambiguation. The algorithm does not need to train on many senses of each word; it uses instead the probability that certain concepts will occur together. That algorithm is then used to index several corpa of documents. Our indexing algorithm does not generally outperform the traditional stem-based tf.idf model