activity
20142026
most citedLearning Features for Offline Handwritten Signature Verification using Deep Convolutional Neural Networks

387 citations · 1.6k across the 48 of their papers we have counts for

collaborators

52 papers

cs.LG2026

Concept Drift from a Causal Perspective

Eduardo V. L. Barboza, Jean Paul Barddal, Robert Sabourin +1

Concept drift is a common phenomenon in real-world data streams, in which changes in the data-generating distribution can degrade predictive model performance. Most existing defini…

cs.CV2026

A Prototypical Signature Approach for Writer-Independent Offline Signature Verification

Kecia G. de Moura, Robert Sabourin, Rafael M. O. Cruz

Offline handwritten signature verification aims to distinguish genuine from forged signatures using static images. Since real forgeries are rarely available, negative samples are u…

cs.DS2026

Online K-d tree for approximate neighborhood search in data streams

Eduardo V. L. Barboza, Robert Sabourin, Rafael M. O. Cruz

The k-Nearest Neighbors (kNN) algorithm has long been widely used in Machine Learning (ML) applications. However, the main concern when using it is the computational cost required…

cs.LG2026

CaDrift: A Time-dependent Causal Generator of Drifting Data Streams

Eduardo V. L. Barboza, Jean Paul Barddal, Robert Sabourin +1

This work presents Causal Drift Generator (CaDrift), a time-dependent synthetic data generator framework based on Structural Causal Models (SCMs). The framework produces a virtuall…

cs.LG2025★ 6 cited

IncA-DES: An incremental and adaptive dynamic ensemble selection approach using online K-d tree neighborhood search for data streams with concept drift

Eduardo V. L. Barboza, Paulo R. Lisboa de Almeida, Alceu de Souza Britto +2

Data streams pose challenges not usually encountered in batch-based ML. One of them is concept drift, which is characterized by the change in data distribution over time. Among man…

cs.CV2024

Offline Handwritten Signature Verification Using a Stream-Based Approach

Kecia G. de Moura, Rafael M. O. Cruz, Robert Sabourin

Handwritten Signature Verification (HSV) systems distinguish between genuine and forged signatures. Traditional HSV development involves a static batch configuration, constraining…

cs.LG2022

Local overlap reduction procedure for dynamic ensemble selection

Mariana A. Souza, Robert Sabourin, George D. C. Cavalcanti +1

Class imbalance is a characteristic known for making learning more challenging for classification models as they may end up biased towards the majority class. A promising approach…

cs.LG2022

Dynamic Ensemble Selection Using Fuzzy Hyperboxes

Reza Davtalab, Rafael M. O. Cruz, Robert Sabourin

Most dynamic ensemble selection (DES) methods utilize the K-Nearest Neighbors (KNN) algorithm to estimate the competence of classifiers in a small region surrounding the query samp…

cs.LG2020

Classifier Pool Generation based on a Two-level Diversity Approach

Marcos Monteiro, Alceu S. Britto, Jean P. Barddal +2

This paper describes a classifier pool generation method guided by the diversity estimated on the data complexity and classifier decisions. First, the behavior of complexity measur…

cs.CV2020

A Comprehensive Comparison of End-to-End Approaches for Handwritten Digit String Recognition

Andre G. Hochuli, Alceu S. Britto, David A. Saji +3

Over the last decades, most approaches proposed for handwritten digit string recognition (HDSR) have resorted to digit segmentation, which is dominated by heuristics, thereby impos…

cs.CV2020

An Investigation of Feature Selection and Transfer Learning for Writer-Independent Offline Handwritten Signature Verification

Victor L. F. Souza, Adriano L. I. Oliveira, Rafael M. O. Cruz +1

SigNet is a state of the art model for feature representation used for handwritten signature verification (HSV). This representation is based on a Deep Convolutional Neural Network…

cs.CV2020

Intrapersonal Parameter Optimization for Offline Handwritten Signature Augmentation

Teruo M. Maruyama, Luiz S. Oliveira, Alceu S. Britto +1

Usually, in a real-world scenario, few signature samples are available to train an automatic signature verification system (ASVS). However, such systems do indeed need a lot of sig…

cs.LG2020★ 2 cited

Random Forest for Dissimilarity-based Multi-view Learning

Simon Bernard, Hongliu Cao, Robert Sabourin +1

Many classification problems are naturally multi-view in the sense their data are described through multiple heterogeneous descriptions. For such tasks, dissimilarity strategies ar…

cs.LG2020★ 3 cited

A Novel Random Forest Dissimilarity Measure for Multi-View Learning

Hongliu Cao, Simon Bernard, Robert Sabourin +1

Multi-view learning is a learning task in which data is described by several concurrent representations. Its main challenge is most often to exploit the complementarities between t…

cs.CV2020

Improving BPSO-based feature selection applied to offline WI handwritten signature verification through overfitting control

Victor L. F. Souza, Adriano L. I. Oliveira, Rafael M. O. Cruz +1

This paper investigates the presence of overfitting when using Binary Particle Swarm Optimization (BPSO) to perform the feature selection in a context of Handwritten Signature Veri…

cs.CV2020

A white-box analysis on the writer-independent dichotomy transformation applied to offline handwritten signature verification

Victor L. F. Souza, Adriano L. I. Oliveira, Rafael M. O. Cruz +1

High number of writers, small number of training samples per writer with high intra-class variability and heavily imbalanced class distributions are among the challenges and diffic…

cs.LG2020

Multi-label learning for dynamic model type recommendation

Mariana A. Souza, Robert Sabourin, George D. C. Cavalcanti +1

Dynamic selection techniques aim at selecting the local experts around each test sample in particular for performing its classification. While generating the classifier on a local…

cs.CV2020★ 10 cited

An End-to-End Approach for Recognition of Modern and Historical Handwritten Numeral Strings

Andre G. Hochuli, Alceu S. Britto, Jean P. Barddal +2

An end-to-end solution for handwritten numeral string recognition is proposed, in which the numeral string is considered as composed of objects automatically detected and recognize…

cs.CV2019

Meta-learning for fast classifier adaptation to new users of Signature Verification systems

Luiz G. Hafemann, Robert Sabourin, Luiz S. Oliveira

Offline Handwritten Signature verification presents a challenging Pattern Recognition problem, where only knowledge of the positive class is available for training. While classifie…

cs.LG2019

A Decision-Based Dynamic Ensemble Selection Method for Concept Drift

Regis Antonio Saraiva Albuquerque, Albert Franca Josua Costa, Eulanda Miranda dos Santos +2

We propose an online method for concept driftdetection based on dynamic classifier ensemble selection. Theproposed method generates a pool of ensembles by promotingdiversity among…

cs.CV2019★ 58 cited

Characterizing and evaluating adversarial examples for Offline Handwritten Signature Verification

Luiz G. Hafemann, Robert Sabourin, Luiz S. Oliveira

The phenomenon of Adversarial Examples is attracting increasing interest from the Machine Learning community, due to its significant impact to the security of Machine Learning syst…

cs.LG2018

ICPRAI 2018 SI: On dynamic ensemble selection and data preprocessing for multi-class imbalance learning

Rafael M. O. Cruz, Mariana A. Souza, Robert Sabourin +1

Class-imbalance refers to classification problems in which many more instances are available for certain classes than for others. Such imbalanced datasets require special attention…

cs.CV2018★ 1 cited

Decoupling Direction and Norm for Efficient Gradient-Based L2 Adversarial Attacks and Defenses

Jérôme Rony, Luiz G. Hafemann, Luiz S. Oliveira +3

Research on adversarial examples in computer vision tasks has shown that small, often imperceptible changes to an image can induce misclassification, which has security implication…

cs.LG2018★ 15 cited

On Meta-Learning for Dynamic Ensemble Selection

Rafael M. O. Cruz, Robert Sabourin, George D. C. Cavalcanti

In this paper, we propose a novel dynamic ensemble selection framework using meta-learning. The framework is divided into three steps. In the first step, the pool of classifiers is…