Performance Analysis of Information Retrieval Systems

International audienceIt has been shown that there is not a best information retrieval system configuration which would work for any query, but rather that performance can vary from one query to another. It would be interesting if a meta-system could decide which system should process a new query by learning from the context of previously submitted queries. This paper reports a deep analysis considering more than 80,000 search engine configurations applied to 100 queries and the corresponding performance. The goal of the analysis is to identify which search engine configuration responds best to a certain type of query. We considered two approaches to define query types: one is based on query clustering according to the query performance (their difficulty), while the other approach uses various query features (including query difficulty predictors) to cluster queries. We identified two parameters that should be optimized first. An important outcome is that we could not obtain strong conclusive results; considering the large number of systems and methods we used, this result could lead to the conclusion that current query features does not fit the optimizing problem

La prédiction efficace de la difficulté des requêtes : une tâche impossible?

National audienceABSTRACT. Search engines found answers whatever the user query is, but some queries are more difficult than others for the system. For difficult queries, adhoc treatments must be applied. Predicting query difficulty is crucial and different predictors have been proposed. In this paper, we revisit these predictors. First we check the non statistical redundancy of predictors. Then, we show that the correlation between the values of predictors and system performance gives little hope on the ability of these predictors to be effective. Finally, we study the ability of predictors to predict the classes of difficulty by relying on a variety of exploratory and learning methods. We show that despite the (low) correlation with performance measures, current predictors are not robust enough to be used in practical IR applications. MOTS-CLÉS : Recherche d'information, requête difficile, prédiction, analyse de données.RÉSUMÉ. Les moteurs de recherche d'information (RI) retrouvent des réponses quelle que soit la requête, mais certaines requêtes sont difficiles (le système n'obtient pas de bonne performance en termes de mesure de RI). Pour les requêtes difficiles, des traitements adhoc doivent être ap-pliqués. Prédire qu'une requête est difficile est donc crucial et différents prédicteurs ont été proposés. Dans cet articlenous étudions la variété de l'information captée par les prédicteurs existants et donc leur non redondance. Par ailleurs, nous montrons que les corrélationsentre les prédicteurs et les performance des systèmes donnent peu d'espoir sur la capacité de ces prédic-teurs à être réellement efficaces. Enfin, nous étudions la capacité des prédicteurs à prédire les classes de difficulté des requêtes en nous appuyant sur une variété de méthodes exploratoires et d'apprentissage. Nous montrons que malgré les (faibles) corrélations observées avec les mesures de performance, les prédicteurs actuels conduisent à des performances de prédiction variables et sont donc difficilement utilisables dans une application concrète de RI

Predicting IR Personalization Performance using Pre-retrieval Query Predictors

Personalization generally improves the performance of queries but in a few cases it may also harms it. If we are able to predict and therefore to disable personalization for those situations, the overall performance will be higher and users will be more satisfied with personalized systems. We use some state-of-the-art pre-retrieval query performance predictors and propose some others including the user profile information for the previous purpose. We study the correlations among these predictors and the difference between the personalized and the original queries. We also use classification and regression techniques to improve the results and finally reach a bit more than one third of the maximum ideal performance. We think this is a good starting point within this research line, which certainly needs more effort and improvements.This work has been supported by the Spanish Andalusian “Consejerı́a de Innovación, Ciencia y Empresa” postdoctoral phase of project P09-TIC-4526, the Spanish “Ministerio de Economı́a y Competitividad” projects TIN2013-42741-P and TIN2016-77902-C3-2-P, and the European Regional Development Fund (ERDF-FEDER)

Query Performance Prediction:From Ad-hoc to Conversational Search

Query performance prediction (QPP) is a core task in information retrieval. The QPP task is to predict the retrieval quality of a search system for a query without relevance judgments. Research has shown the effectiveness and usefulness of QPP for ad-hoc search. Recent years have witnessed considerable progress in conversational search (CS). Effective QPP could help a CS system to decide an appropriate action to be taken at the next turn. Despite its potential, QPP for CS has been little studied. We address this research gap by reproducing and studying the effectiveness of existing QPP methods in the context of CS. While the task of passage retrieval remains the same in the two settings, a user query in CS depends on the conversational history, introducing novel QPP challenges. In particular, we seek to explore to what extent findings from QPP methods for ad-hoc search generalize to three CS settings: (i) estimating the retrieval quality of different query rewriting-based retrieval methods, (ii) estimating the retrieval quality of a conversational dense retrieval method, and (iii) estimating the retrieval quality for top ranks vs. deeper-ranked lists. Our findings can be summarized as follows: (i) supervised QPP methods distinctly outperform unsupervised counterparts only when a large-scale training set is available; (ii) point-wise supervised QPP methods outperform their list-wise counterparts in most cases; and (iii) retrieval score-based unsupervised QPP methods show high effectiveness in assessing the conversational dense retrieval method, ConvDR.</p

Performance Prediction for Multi-hop Questions

We study the problem of Query Performance Prediction (QPP) for open-domain multi-hop Question Answering (QA), where the task is to estimate the difficulty of evaluating a multi-hop question over a corpus. Despite the extensive research on predicting the performance of ad-hoc and QA retrieval models, there has been a lack of study on the estimation of the difficulty of multi-hop questions. The problem is challenging due to the multi-step nature of the retrieval process, potential dependency of the steps and the reasoning involved. To tackle this challenge, we propose multHP, a novel pre-retrieval method for predicting the performance of open-domain multi-hop questions. Our extensive evaluation on the largest multi-hop QA dataset using several modern QA systems shows that the proposed model is a strong predictor of the performance, outperforming traditional single-hop QPP models. Additionally, we demonstrate that our approach can be effectively used to optimize the parameters of QA systems, such as the number of documents to be retrieved, resulting in improved overall retrieval performance.Comment: 10 page

Predicting IR Personalization Performance using Pre-retrieval Query Predictors

Personalization generally improves the performance of queries but in a few cases it may also harms it. If we are able to predict and therefore to disable personalization for those situations, the overall performance will be higher and users will be more satisfied with personalized systems. We use some state-of-the-art pre-retrieval query performance predictors and propose some others including the user profile information for the previous purpose. We study the correlations among these predictors and the difference between the personalized and the original queries. We also use classification and regression techniques to improve the results and finally reach a bit more than one third of the maximum ideal performance. We think this is a good starting point within this research line, which certainly needs more effort and improvements

iQPP: A Benchmark for Image Query Performance Prediction

To date, query performance prediction (QPP) in the context of content-based image retrieval remains a largely unexplored task, especially in the query-by-example scenario, where the query is an image. To boost the exploration of the QPP task in image retrieval, we propose the first benchmark for image query performance prediction (iQPP). First, we establish a set of four data sets (PASCAL VOC 2012, Caltech-101, ROxford5k and RParis6k) and estimate the ground-truth difficulty of each query as the average precision or the precision@k, using two state-of-the-art image retrieval models. Next, we propose and evaluate novel pre-retrieval and post-retrieval query performance predictors, comparing them with existing or adapted (from text to image) predictors. The empirical results show that most predictors do not generalize across evaluation scenarios. Our comprehensive experiments indicate that iQPP is a challenging benchmark, revealing an important research gap that needs to be addressed in future work. We release our code and data as open source at https://github.com/Eduard6421/iQPP, to foster future research.Comment: Accepted at SIGIR 202

A Wikipedia powered state-based approach to automatic search query enhancement

This paper describes the development and testing of a novel Automatic Search Query Enhancement (ASQE) algorithm, the Wikipedia N Sub-state Algorithm (WNSSA), which utilises Wikipedia as the sole data source for prior knowledge. This algorithm is built upon the concept of iterative states and sub-states, harnessing the power of Wikipedia\u27s data set and link information to identify and utilise reoccurring terms to aid term selection and weighting during enhancement. This algorithm is designed to prevent query drift by making callbacks to the user\u27s original search intent by persisting the original query between internal states with additional selected enhancement terms. The developed algorithm has shown to improve both short and long queries by providing a better understanding of the query and available data. The proposed algorithm was compared against five existing ASQE algorithms that utilise Wikipedia as the sole data source, showing an average Mean Average Precision (MAP) improvement of 0.273 over the tested existing ASQE algorithms