South America
Regularization Through Simultaneous Learning: A Case Study on Plant Classification
Castro, Pedro Henrique Nascimento, Fortuna, Gabriel Cássia, de Queiroz, Rafael Alves Bonfim, Moreira, Gladston Juliano Prates, Luz, Eduardo José da Silva
In response to the prevalent challenge of overfitting in deep neural networks, this paper introduces Simultaneous Learning, a regularization approach drawing on principles of Transfer Learning and Multi-task Learning. We leverage auxiliary datasets with the target dataset, the UFOP-HVD, to facilitate simultaneous classification guided by a customized loss function featuring an inter-group penalty. This experimental configuration allows for a detailed examination of model performance across similar (PlantNet) and dissimilar (ImageNet) domains, thereby enriching the generalizability of Convolutional Neural Network models. Remarkably, our approach demonstrates superior performance over models without regularization and those applying dropout regularization exclusively, enhancing accuracy by 5 to 22 percentage points. Moreover, when combined with dropout, the proposed approach improves generalization, securing state-of-the-art results for the UFOP-HVD challenge. The method also showcases efficiency with significantly smaller sample sizes, suggesting its broad applicability across a spectrum of related tasks. In addition, an interpretability approach is deployed to evaluate feature quality by analyzing class feature correlations within the network's convolutional layers. The findings of this study provide deeper insights into the efficacy of Simultaneous Learning, particularly concerning its interaction with the auxiliary and target datasets.
Advancing Neural Encoding of Portuguese with Transformer Albertina PT-*
Rodrigues, João, Gomes, Luís, Silva, João, Branco, António, Santos, Rodrigo, Cardoso, Henrique Lopes, Osório, Tomás
In recent years, the field of Artificial Intelligence has come to successfully exploit the paradigm of deep learning, a machine learning approach based on large artificial neural networks [LeCun et al., 2015]. Applied to Natural Language Processing (NLP), deep learning gained outstanding traction with notable breakthroughs under the distributional semantics approach, namely with word embedding techniques [Mikolov et al., 2013] and the Transformer neural architecture [Vaswani et al., 2017]. These neural models acquire semantic representations from massive amounts of data in a self-supervised learning process that ultimately results in the so-called Foundation Models [Bommasani et al., 2021]. Self-supervision is accomplished in NLP through language modeling [Bengio et al., 2000] and was initially adopted in shallow neural network models such as Word2Vec [Mikolov et al., 2013] for the creation of word embeddings. Over time, this approach was scaled beyond the single-token level to sequence transduction with encoding-decoding models based on recurrent [Sutskever et al., 2014] or convolution neural networks and occasionally supported by attention mechanisms [Bahdanau et al., 2015]. A particular neural network architecture, the Transformer, has stood out among all others, showing superior performance by a large margin, sometimes even surpassing human-level performance [Wang et al., 2018, Wang et al., 2019], and became mainstream in virtually every NLP task and application [Bommasani et al., 2021]. Several variants have spun out from the base Transformer architecture (encoder-decoder), including the landmark encoder BERT [Devlin et al., 2019] and the outstanding decoder GPT [Brown et al., 2020], which have been most successfully adapted to downstream
Mirror Sinkhorn: Fast Online Optimization on Transport Polytopes
Ballu, Marin, Berthet, Quentin
Gromov-Wasserstein problems (Mémoli, 2011; Solomon et al., 2016)) and for computing euclidean projection on the Optimal transport is an important tool in machine Birkhoff polytope (Li et al., 2020). It appears in statistical learning, allowing to capture geometric properties inference on random permutations (Birdal & Simsekli, of the data through a linear program on transport 2019). Inference on random permutations can be obtained polytopes. We present a single-loop optimization by minimizing various other convex functions (Linderman algorithm for minimizing general convex objectives et al., 2018). Optimisation on this polytope also arises when on these domains, utilizing the principles trying to both compute and minimize a Wasserstein distance of Sinkhorn matrix scaling and mirror descent.
Multi-aspect Multilingual and Cross-lingual Parliamentary Speech Analysis
Miok, Kristian, Hidalgo-Tenorio, Encarnacion, Osenova, Petya, Benitez-Castro, Miguel-Angel, Robnik-Sikonja, Marko
Parliamentary and legislative debate transcripts provide informative insight into elected politicians' opinions, positions, and policy preferences. They are interesting for political and social sciences as well as linguistics and natural language processing (NLP) research. While existing research studied individual parliaments, we apply advanced NLP methods to a joint and comparative analysis of six national parliaments (Bulgarian, Czech, French, Slovene, Spanish, and United Kingdom) between 2017 and 2020. We analyze emotions and sentiment in the transcripts from the ParlaMint dataset collection and assess if the age, gender, and political orientation of speakers can be detected from their speeches. The results show some commonalities and many surprising differences among the analyzed countries.
A Survey on Deep Learning for Skin Lesion Segmentation
Mirikharaji, Zahra, Abhishek, Kumar, Bissoto, Alceu, Barata, Catarina, Avila, Sandra, Valle, Eduardo, Celebi, M. Emre, Hamarneh, Ghassan
Skin cancer is a major public health problem that could benefit from computer-aided diagnosis to reduce the burden of this common disease. Skin lesion segmentation from images is an important step toward achieving this goal. However, the presence of natural and artificial artifacts (e.g., hair and air bubbles), intrinsic factors (e.g., lesion shape and contrast), and variations in image acquisition conditions make skin lesion segmentation a challenging task. Recently, various researchers have explored the applicability of deep learning models to skin lesion segmentation. In this survey, we cross-examine 177 research papers that deal with deep learning-based segmentation of skin lesions. We analyze these works along several dimensions, including input data (datasets, preprocessing, and synthetic data generation), model design (architecture, modules, and losses), and evaluation aspects (data annotation requirements and segmentation performance). We discuss these dimensions both from the viewpoint of select seminal works, and from a systematic viewpoint, examining how those choices have influenced current trends, and how their limitations should be addressed. To facilitate comparisons, we summarize all examined works in a comprehensive table as well as an interactive table available online at https://github.com/sfu-mial/skin-lesion-segmentation-survey.
Multilingual Few-Shot Learning via Language Model Retrieval
Winata, Genta Indra, Huang, Liang-Kang, Vadlamannati, Soumya, Chandarana, Yash
Transformer-based language models have achieved remarkable success in few-shot in-context learning and drawn a lot of research interest. However, these models' performance greatly depends on the choice of the example prompts and also has high variability depending on how samples are chosen. In this paper, we conduct a comprehensive study of retrieving semantically similar few-shot samples and using them as the context, as it helps the model decide the correct label without any gradient update in the multilingual and cross-lingual settings. We evaluate the proposed method on five natural language understanding datasets related to intent detection, question classification, sentiment analysis, and topic classification. The proposed method consistently outperforms random sampling in monolingual and cross-lingual tasks in non-English languages.
Deep learning applied to computational mechanics: A comprehensive review, state of the art, and the classics
Vu-Quoc, Loc, Humer, Alexander
Three recent breakthroughs due to AI in arts and science serve as motivation: An award winning digital image, protein folding, fast matrix multiplication. Many recent developments in artificial neural networks, particularly deep learning (DL), applied and relevant to computational mechanics (solid, fluids, finite-element technology) are reviewed in detail. Both hybrid and pure machine learning (ML) methods are discussed. Hybrid methods combine traditional PDE discretizations with ML methods either (1) to help model complex nonlinear constitutive relations, (2) to nonlinearly reduce the model order for efficient simulation (turbulence), or (3) to accelerate the simulation by predicting certain components in the traditional integration methods. Here, methods (1) and (2) relied on Long-Short-Term Memory (LSTM) architecture, with method (3) relying on convolutional neural networks. Pure ML methods to solve (nonlinear) PDEs are represented by Physics-Informed Neural network (PINN) methods, which could be combined with attention mechanism to address discontinuous solutions. Both LSTM and attention architectures, together with modern and generalized classic optimizers to include stochasticity for DL networks, are extensively reviewed. Kernel machines, including Gaussian processes, are provided to sufficient depth for more advanced works such as shallow networks with infinite width. Not only addressing experts, readers are assumed familiar with computational mechanics, but not with DL, whose concepts and applications are built up from the basics, aiming at bringing first-time learners quickly to the forefront of research. History and limitations of AI are recounted and discussed, with particular attention at pointing out misstatements or misconceptions of the classics, even in well-known references. Positioning and pointing control of a large-deformable beam is given as an example.
Planning as Theorem Proving with Heuristics
Soutchanski, Mikhail, Young, Ryan
Planning as theorem proving in situation calculus was abandoned 50 years ago as an impossible project. But we have developed a Theorem Proving Lifted Heuristic (TPLH) planner that searches for a plan in a tree of situations using the A* search algorithm. It is controlled by a delete relaxation-based domain independent heuristic. We compare TPLH with Fast Downward (FD) and Best First Width Search (BFWS) planners over several standard benchmarks. Since our implementation of the heuristic function is not optimized, TPLH is slower than FD and BFWS. But it computes shorter plans, and it explores fewer states. We discuss previous research on planning within KR\&R and identify related directions. Thus, we show that deductive lifted heuristic planning in situation calculus is actually doable.
Balancing Utility and Fairness in Submodular Maximization (Technical Report)
Wang, Yanhao, Li, Yuchen, Bonchi, Francesco, Wang, Ying
Submodular function maximization is a fundamental combinatorial optimization problem with plenty of applications -- including data summarization, influence maximization, and recommendation. In many of these problems, the goal is to find a solution that maximizes the average utility over all users, for each of whom the utility is defined by a monotone submodular function. However, when the population of users is composed of several demographic groups, another critical problem is whether the utility is fairly distributed across different groups. Although the \emph{utility} and \emph{fairness} objectives are both desirable, they might contradict each other, and, to the best of our knowledge, little attention has been paid to optimizing them jointly. To fill this gap, we propose a new problem called \emph{Bicriteria Submodular Maximization} (BSM) to balance utility and fairness. Specifically, it requires finding a fixed-size solution to maximize the utility function, subject to the value of the fairness function not being below a threshold. Since BSM is inapproximable within any constant factor, we focus on designing efficient instance-dependent approximation schemes. Our algorithmic proposal comprises two methods, with different approximation factors, obtained by converting a BSM instance into other submodular optimization problem instances. Using real-world and synthetic datasets, we showcase applications of our proposed methods in three submodular maximization problems: maximum coverage, influence maximization, and facility location.
FSUIE: A Novel Fuzzy Span Mechanism for Universal Information Extraction
Peng, Tianshuo, Li, Zuchao, Zhang, Lefei, Du, Bo, Zhao, Hai
Universal Information Extraction (UIE) has been introduced as a unified framework for various Information Extraction (IE) tasks and has achieved widespread success. Despite this, UIE models have limitations. For example, they rely heavily on span boundaries in the data during training, which does not reflect the reality of span annotation challenges. Slight adjustments to positions can also meet requirements. Additionally, UIE models lack attention to the limited span length feature in IE. To address these deficiencies, we propose the Fuzzy Span Universal Information Extraction (FSUIE) framework. Specifically, our contribution consists of two concepts: fuzzy span loss and fuzzy span attention. Our experimental results on a series of main IE tasks show significant improvement compared to the baseline, especially in terms of fast convergence and strong performance with small amounts of data and training epochs. These results demonstrate the effectiveness and generalization of FSUIE in different tasks, settings, and scenarios.