Cookies
O website necessita de alguns cookies e outros recursos semelhantes para funcionar. Caso o permita, o INESC TEC irá utilizar cookies para recolher dados sobre as suas visitas, contribuindo, assim, para estatísticas agregadas que permitem melhorar o nosso serviço. Ver mais
Aceitar Rejeitar
  • Menu
Publicações

Publicações por Alípio Jorge

2001

Collaboration support for virtual data mining enterprises

Autores
Voß, A; Richter, G; Moyle, S; Jorge, A;

Publicação
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Abstract
RAMSYS is a web-based infrastructure for collaborative data mining. It is being developed in the SolEuNet European Project for virtual enterprise services in data mining and decision support. Central to RAMSYS is the idea of sharing the current best understanding to foster efficient collaboration. This paper presents the design and rationale of Zeno, a core component of RAMSYS. Zeno is a groupware for discourses on the Internet and, for RAMSYS, aims to provide a “virtual data mining laboratory” to aid data miners in collaboratively producing better solutions to data mining problems. © Springer-Verlag Berlin Heidelberg 2001.

2012

Enriching temporal query understanding through date identification: How to tag implicit temporal queries?

Autores
Campos, R; Dias, G; Jorge, AM; Nunes, C;

Publicação
ACM International Conference Proceeding Series

Abstract
Generically, search engines fail to understand the user's temporal intents when expressed as implicit temporal queries. This causes the retrieval of less relevant information and prevents users from being aware of the possible temporal dimension of the query results. In this paper, we aim to develop a language-independent model that tackles the temporal dimensions of a query and identifies its most relevant time periods. For this purpose, we propose a temporal similarity measure capable of associating a relevant date(s) to a given query and filtering out irrelevant ones. Our approach is based on the exploitation of temporal information from web content, particularly within the set of k-top retrieved web snippets returned in response to a query. We particularly focus on extracting years, which are a kind of temporal information that often appears in this type of collection. We evaluate our methodology using a set of real-world text temporal queries, which are clear concepts (i.e. queries which are non-ambiguous in concept and temporal in their purpose). Experiments show that when compared to baseline methods, determining the most relevant dates relating to any given implicit temporal query can be improved with a new temporal similarity measure. © 2012 ACM.

2009

Ensemble Learning: A Study on Different Variants of the Dynamic Selection Approach

Autores
Mendes Moreira, J; Jorge, AM; Soares, C; de Sousa, JF;

Publicação
MACHINE LEARNING AND DATA MINING IN PATTERN RECOGNITION

Abstract
Integration methods for ensemble learning can use two different approaches: combination or selection. The combination approach (also called fusion) consists on the combination of the predictions obtained by different models in the ensemble to obtain the final ensemble predication. The selection approach selects one (or more) models from the ensemble according to the prediction performance of these models on similar data from the validation set. Usually, the method to select similar data is the k-nearest neighbors with the Euclidean distance. In this paper we discuss other approaches to obtain similar data for the regression problem. We show that using similarity measures according to the target values improves results. We also show that selecting dynamically several models for the prediction task increases prediction accuracy comparing to the selection of just one model.

2011

Mining Association Rules for Label Ranking

Autores
de Sa, CR; Soares, C; Jorge, AM; Azevedo, P; Costa, J;

Publicação
ADVANCES IN KNOWLEDGE DISCOVERY AND DATA MINING, PT II: 15TH PACIFIC-ASIA CONFERENCE, PAKDD 2011

Abstract
Recently, a number of learning algorithms have been adapted for label ranking, including instance-based and tree-based methods. In this paper, we propose an adaptation of association rules for label ranking. The adaptation, which is illustrated in this work with APRIORI Algorithm, essentially consists of using variations of the support and confidence measures based on ranking similarity functions that are suitable for label ranking. We also adapt the method to make a prediction from the possibly conflicting consequents of the rules that apply to an example. Despite having made our adaptation from a very simple variant of association rules for classification, the results clearly show that the method is making valid predictions. Additionally, they show that it competes well with state-of-the-art label ranking algorithms.

2000

Integrating rules and cases in learning via case explanation and paradigm shift

Autores
Lopes, AD; Jorge, A;

Publicação
ADVANCES IN ARTIFICIAL INTELLIGENCE

Abstract
In this article we discuss in detail two techniques for rule and case integration. Case-based learning is used when the rule language is exhausted. Initially, all the examples are used to induce a set of rules with satisfactory quality. The examples that are not covered by these rules are then handled as cases. The case-based approach used also combines rules and cases internally. Instead of only storing the cases as provided, it has a learning phase where, for each case, it constructs and stores a set of explanations with support and confidence above given thresholds. These explanations have different levels of generality and the maximally specific one corresponds to the case itself. The same case may have different explanations representing different perspectives of the case. Therefore, to classify a new case, it looks for relevant stored explanations applicable to the new case. The different possible views of the case given by the explanations correspond to considering different sets of conditions/features to analyze the case. In other words, they lead to different ways to compute similarity between known cases/explanations and the new case to be classified (as opposed to the commonly used fixed metric).

2012

Combining usage and content in an online music recommendation system for music in the long-tail

Autores
Domingues, MA; Gouyon, F; Jorge, AM; Leal, JP; Vinagre, J; Lemos, L; Sordo, M;

Publicação
WWW'12 - Proceedings of the 21st Annual Conference on World Wide Web Companion

Abstract
In this paper we propose a hybrid music recommender system, which combines usage and content data. We describe an online evaluation experiment performed in real time on a commercial music web site, specialised in content from the very long tail of music content. We compare it against two stand-alone recommenders, the first system based on usage and the second one based on content data. The results show that the proposed hybrid recommender shows advantages with respect to usage- and content-based systems, namely, higher user absolute acceptance rate, higher user activity rate and higher user loyalty. Copyright is held by the International World Wide Web Conference Committee (IW3C2).

  • 26
  • 40