26 research outputs found
Teaching a New Dog Old Tricks: Resurrecting Multilingual Retrieval Using Zero-shot Learning
While billions of non-English speaking users rely on search engines every
day, the problem of ad-hoc information retrieval is rarely studied for
non-English languages. This is primarily due to a lack of data set that are
suitable to train ranking algorithms. In this paper, we tackle the lack of data
by leveraging pre-trained multilingual language models to transfer a retrieval
system trained on English collections to non-English queries and documents. Our
model is evaluated in a zero-shot setting, meaning that we use them to predict
relevance scores for query-document pairs in languages never seen during
training. Our results show that the proposed approach can significantly
outperform unsupervised retrieval techniques for Arabic, Chinese Mandarin, and
Spanish. We also show that augmenting the English training collection with some
examples from the target language can sometimes improve performance.Comment: ECIR 2020 (short
Selective relevance feedback using term characteristics
This paper presents a new relevance feedback technique; selectively combining evidence based on the usage of terms within documents. By considering how terms are used within documents, we can better describe the features that might make a document relevant and thus improve retrieval effectiveness. In this paper we present an initial, experimental investigation of this technique, incorporating new and existing measures for describing the information content of a document. The results from these experiments positively support our hypothesis that extending relevance feedback to take into account how terms are used within documents can improve the performance of relevance feedback
The accessibility dimension for structured document retrieval
Structured document retrieval aims at retrieving the document components that best satisfy a query, instead of merely retrieving pre-defined document units. This paper reports on an investigation of a tf-idf-acc approach, where tf and idf are the classical term frequency and inverse document frequency, and acc, a new parameter called accessibility, that captures the structure of documents. The tf-idf-acc approach is defined using a probabilistic relational algebra. To investigate the retrieval quality and estimate the acc values, we developed a method that automatically constructs diverse test collections of structured documents from a standard test collection, with which experiments were carried out. The analysis of the experiments provides estimates of the acc values
Automatic Ranking of Retrieval Systems in Imperfect Environments
The empirical investigation of the effectiveness of information retrieval (IR) systems requires a test collection, a set of query topics, and a set of relevance judgments made by human assessors for each query. Previous experiments show that differences in human relevance assessments do not affect the relative performance of retrieval systems. Based on this observation, we propose and evaluate a new approach to replace the human relevance judgments by an automatic method. Ranking of retrieval systems with our methodology correlates positively and significantly with that of human-based evaluations. In the experiments, we assume a Web-like imperfect environment: the indexing information for all documents is available for ranking, but some documents may not be available for retrieval. Such conditions can be due to document deletions or network problems. Our method of simulating imperfect environments can be used for Web search engine assessment and in estimating the effects of network conditions (e.g., network unreliability) on IR system performance
Users' perception of relevance of spoken documents
We present the results of a study of user's perception of relevance of documents. The aim is to study experimentally how users' perception varies depending on the form that retrieved documents are presented. Documents retrieved in response to a query are presented to users in a variety of ways, from full text to a machine spoken query-biased automatically-generated summary, and the difference in users' perception of relevance is studied. The experimental results suggest that the effectiveness of advanced multimedia information retrieval applications may be affected by the low level of users' perception of relevance of retrieved documents
Probabilistic learning for selective dissemination of information
New methods and new systems are needed to filter or to selectively distribute the increasing volume of electronic information being produced nowadays. An effective information filtering system is one that provides the exact information that fulfills user's interests with the minimum effort by the user to describe it. Such a system will have to be adaptive to the user changing interest. In this paper we describe and evaluate a learning model for information filtering which is an adaptation of the generalized probabilistic model of information retrieval. The model is based on the concept of 'uncertainty sampling', a technique that allows for relevance feedback both on relevant and nonrelevant documents. The proposed learning model is the core of a prototype information filtering system called ProFile
Learning Analogies and Semantic Relations
We present an algorithm for learning from unlabeled text, based on the
Vector Space Model (VSM) of information retrieval, that can solve verbal
analogy questions of the kind found in the Scholastic Aptitude Test (SAT).
A verbal analogy has the form A:B::C:D, meaning "A is to B as C is to D";
for example, mason:stone::carpenter:wood. SAT analogy questions provide
a word pair, A:B, and the problem is to select the most analogous word
pair, C:D, from a set of five choices. The VSM algorithm correctly
answers 47% of a collection of 374 college-level analogy questions
(random guessing would yield 20% correct). We motivate this research by
relating it to work in cognitive science and linguistics, and by applying
it to a difficult problem in natural language processing, determining
semantic relations in noun-modifier pairs. The problem is to classify a
noun-modifier pair, such as "laser printer", according to the semantic
relation between the noun (printer) and the modifier (laser). We use a
supervised nearest-neighbour algorithm that assigns a class to a given
noun-modifier pair by finding the most analogous noun-modifier pair in
the training data. With 30 classes of semantic relations, on a collection
of 600 labeled noun-modifier pairs, the learning algorithm attains an F
value of 26.5% (random guessing: 3.3%). With 5 classes of semantic
relations, the F value is 43.2% (random: 20%). The performance is
state-of-the-art for these challenging problems
Combining and selecting characteristics of information use
In this paper we report on a series of experiments designed to investigate the combination of term and document weighting functions in Information Retrieval. We describe a series of weighting functions, each of which is based on how information is used within documents and collections, and use these weighting functions in two types of experiments: one based on combination of evidence for ad-hoc retrieval, the other based on selective combination of evidence within a relevance feedback situation. We discuss the difficulties involved in predicting good combinations of evidence for ad-hoc retrieval, and suggest the factors that may lead to the success or failure of combination. We also demonstrate how, in a relevance feedback situation, the relevance assessments can provide a good indication of how evidence should be selected for query term weighting. The use of relevance information to guide the combination process is shown to reduce the variability inherent in combination of evidence
Recall, Robustness, and Lexicographic Evaluation
Researchers use recall to evaluate rankings across a variety of retrieval,
recommendation, and machine learning tasks. While there is a colloquial
interpretation of recall in set-based evaluation, the research community is far
from a principled understanding of recall metrics for rankings. The lack of
principled understanding of or motivation for recall has resulted in criticism
amongst the retrieval community that recall is useful as a measure at all. In
this light, we reflect on the measurement of recall in rankings from a formal
perspective. Our analysis is composed of three tenets: recall, robustness, and
lexicographic evaluation. First, we formally define `recall-orientation' as
sensitivity to movement of the bottom-ranked relevant item. Second, we analyze
our concept of recall orientation from the perspective of robustness with
respect to possible searchers and content providers. Finally, we extend this
conceptual and theoretical treatment of recall by developing a practical
preference-based evaluation method based on lexicographic comparison. Through
extensive empirical analysis across 17 TREC tracks, we establish that our new
evaluation method, lexirecall, is correlated with existing recall metrics and
exhibits substantially higher discriminative power and stability in the
presence of missing labels. Our conceptual, theoretical, and empirical analysis
substantially deepens our understanding of recall and motivates its adoption
through connections to robustness and fairness.Comment: Under revie