Cookies Policy
The website need some cookies and similar means to function. If you permit us, we will use those means to collect data on your visits for aggregated statistics to improve our service. Find out More
Accept Reject
  • Menu
Facts & Numbers
000
Presentation

Artificial Intelligence and Decision Support

At LIAAD, we work on the very strategic area of Data Science, which has an increasing interest worldwide and is critical to all areas of human activity. The huge amounts of collected data (Big Data) and the ubiquity of devices with sensors and/or processing power offer opportunities and challenges to scientists and engineers. Moreover, the demand for complex models for objective decision support is spreading in business, health, science, e-government and e-learning, which encourages us to invest in different approaches to modelling.

Our overall strategy is to take advantage of the data flood and diversification, and to invest in research lines that will help reduce the gap between collected and useful data, while offering diverse modelling solutions.

At LIAAD, our fundamental scientific principals are machine learning, statistics, optimisation and mathematics.

Latest News
Computer Science and Engineering

Less common language varieties also have a place in the era of AI, as demonstrated by two INESC TEC papers presented at a top conference

It's hard to think of current technologies or innovations that do not resort to Language Models (LM) or Natural Language Processing (NLP). Their presence in various society domains - some with significant relevance, like the legal or healthcare sectors - raise issues (and concerns) that often end up focusing on the same question: are LM-based technologies reaching all communities? Recently, two scientific papers featuring INESC TEC - both accepted at AAAI, an A* conference - sought to address some of the challenges in this new era, which directly influence the Portuguese language.

28th February 2025

Computer Science and Engineering

Tell me what you're looking for and I'll tell you what you need. INESC TEC-Amazon collaboration optimises search engine results for special dates

The seasonality of search queries in search engines could be a factor for online businesses to consider if they seek to improve the ranking of their results. A new demo-paper featuring INESC TEC explored the creation of a database to present the Occasion-aware Recommender solution.

26th February 2025

Computer Science and Engineering

INESC TEC developed natural language processing resources for the Portuguese language

The main goal of the PTicola project was to expand and build new Natural Language Processing (NLP) capabilities for the Portuguese language. The results of this project - which include, for example, an English/European Portuguese translator and a PT-BR/PT-PT language variety identifier - address the gap in NLP resources available for PT-PT compared to PT-BR.

14th February 2025

Artificial Intelligence

The largest machine learning conference in Europe will take place in Porto and is now accepting papers

It is called ECML PKDD - European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases -, and it is the largest European conference in machine learning. The event, promoted by INESC TEC, will take place between September 15 and 19, 2025, in Porto; the submission of papers is open until March.

09th January 2025

Artificial Intelligence

"Where do We Come From? Where are We Going?": that's how João Gama - one of the most-cited scientists in the world - said “goodbye” to his teaching activity

35 years separate the beginning and the end of the teaching career of João Gama, one of the most-cited scientists in the world. The INESC TEC researcher, who presented his Last Lecture on November 25, said “goodbye” to the classrooms of the Faculty of Economics of the University of Porto (FEP). The motto? "Where do We Come From? Where are we going?” – the culmination of a recognised academic career, particularly in the fields of Artificial Intelligence (AI) and Machine Learning.

28th November 2024

003

Featured Projects

PROD_AI

Solução IA/ML preditiva aplicada ao procurement e gestão de produção:

2025-2027

Doc2FraudDetection

Automated Detection of Fraudulent Documents

2025-2026

Easy4ALL

AI Assistant for No-Code Plataform

2024-2026

Team
Publications

LIAAD Publications

View all Publications

2025

Anomaly Detection in Pet Behavioural Data

Authors
Silva, I; Ribeiro, RP; Gama, J;

Publication
MACHINE LEARNING AND PRINCIPLES AND PRACTICE OF KNOWLEDGE DISCOVERY IN DATABASES, ECML PKDD 2023, PT II

Abstract
Pet owners are increasingly becoming conscious of their pet's necessities and are paying more attention to their overall wellness. The well-being of their pets is intricately linked to their own emotional and physical well-being. Some veterinary system solutions are emerging to provide proactive healthcare options for pets. One such solution offers the continuous monitoring of a pet's activity through accelerometer tracking devices. Based on data collected by this application, in this paper, we study different time aggregation and three unsupervised machine learning techniques to identify anomalies in pet behaviour data. Specifically, three algorithms, Isolation Forest, Local Outlier Factor, and K-Nearest Neighbour, with various thresholds to differentiate between normal and abnormal events. Results conducted on ten pets (five cats and five dogs) show that the most effective approach is to use daily data divided into periods. Moreover, the Local Outlier Factor is the best algorithm for detecting anomalies when prioritizing the identification of true positives. However, it also produces a high false positive ratio.

2025

Data Science for Fighting Environmental Crime

Authors
Barbosa, M; Ribeiro, C; Gomes, F; Ribeiro, RP; Gama, J;

Publication
MACHINE LEARNING AND PRINCIPLES AND PRACTICE OF KNOWLEDGE DISCOVERY IN DATABASES, ECML PKDD 2023, PT II

Abstract
The rise of environmental crimes has become a major concern globally as they cause significant damage to ecosystems, public health and result in economic losses. The availability of vast sensor data provides an opportunity to analyze environmental data proactively. This helps to detect irregularities and uncover potential criminal activities. This paper highlights the critical role played by machine learning (ML) and remote sensing technologies in the continuously evolving scenarios of environmental crime. By examining some case studies on detecting illegal fishing, illegal oil spills, illegal landfills, and illegal logging, we delve into the practical implementation of data-driven approaches for environmental crime detection. Our goal with this study is to provide an overview of the existing research in this area and foster the use of ML and data science techniques to enhance environmental crime detection.

2025

Parametric models for distributional data

Authors
Brito, P; Silva, APD;

Publication
ADVANCES IN DATA ANALYSIS AND CLASSIFICATION

Abstract
We present parametric probabilistic models for numerical distributional variables. The proposed models are based on the representation of each distribution by a location measure and inter-quantile ranges, for given quantiles, thereby characterizing the underlying empirical distributions in a flexible way. Multivariate Normal distributions are assumed for the whole set of indicators, considering alternative structures of the variance-covariance matrix. For all cases, maximum likelihood estimators of the corresponding parameters are derived. This modelling allows for hypothesis testing and multivariate parametric analysis. The proposed framework is applied to Analysis of Variance and parametric Discriminant Analysis of distributional data. A simulation study examines the performance of the proposed models in classification problems under different data conditions. Applications to Internet traffic data and Portuguese official data illustrate the relevance of the proposed approach.

2025

Forecasting with Deep Learning: Beyond Average of Average of Average Performance

Authors
Cerqueira, V; Roque, L; Soares, C;

Publication
DISCOVERY SCIENCE, DS 2024, PT I

Abstract
Accurate evaluation of forecasting models is essential for ensuring reliable predictions. Current practices for evaluating and comparing forecasting models focus on summarising performance into a single score, using metrics such as SMAPE. We hypothesize that averaging performance over all samples dilutes relevant information about the relative performance of models. Particularly, conditions in which this relative performance is different than the overall accuracy. We address this limitation by proposing a novel framework for evaluating univariate time series forecasting models from multiple perspectives, such as one-step ahead forecasting versus multi-step ahead forecasting. We show the advantages of this framework by comparing a state-of-the-art deep learning approach with classical forecasting techniques. While classical methods (e.g. ARIMA) are long-standing approaches to forecasting, deep neural networks (e.g. NHITS) have recently shown state-of-the-art forecasting performance in benchmark datasets. We conducted extensive experiments that show NHITS generally performs best, but its superiority varies with forecasting conditions. For instance, concerning the forecasting horizon, NHITS only outperforms classical approaches for multi-step ahead forecasting. Another relevant insight is that, when dealing with anomalies, NHITS is outperformed by methods such as Theta. These findings highlight the importance of evaluating forecasts from multiple dimensions.

2025

PrivateCTGAN: Adapting GAN for Privacy-Aware Tabular Data Sharing

Authors
Lopes, F; Soares, C; Cortez, P;

Publication
MACHINE LEARNING AND PRINCIPLES AND PRACTICE OF KNOWLEDGE DISCOVERY IN DATABASES, ECML PKDD 2023, PT II

Abstract
This research addresses the challenge of generating synthetic data that resembles real-world data while preserving privacy. With privacy laws protecting sensitive information such as healthcare data, accessing sufficient training data becomes difficult, resulting in an increased difficulty in training Machine Learning models and in overall worst models. Recently, there has been an increased interest in the usage of Generative Adversarial Networks (GAN) to generate synthetic data since they enable researchers to generate more data to train their models. GANs, however, may not be suitable for privacy-sensitive data since they have no concern for the privacy of the generated data. We propose modifying the known Conditional Tabular GAN (CTGAN) model by incorporating a privacy-aware loss function, thus resulting in the Private CTGAN (PCTGAN) method. Several experiments were carried out using 10 public domain classification datasets and comparing PCTGAN with CTGAN and the state-of-the-art privacy-preserving model, the Differential Privacy CTGAN (DP-CTGAN). The results demonstrated that PCTGAN enables users to fine-tune the privacy fidelity trade-off by leveraging parameters, as well as that if desired, a higher level of privacy.

Facts & Figures

0R&D Employees

2020

19Papers in indexed journals

2020

29Senior Researchers

2016