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 Inductive Learning


Combining Abstract Argumentation and Machine Learning for Efficiently Analyzing Low-Level Process Event Streams

arXiv.org Artificial Intelligence

Monitoring and analyzing process traces is a critical task for modern companies and organizations. In scenarios where there is a gap between trace events and reference business activities, this entails an interpretation problem, amounting to translating each event of any ongoing trace into the corresponding step of the activity instance. Building on a recent approach that frames the interpretation problem as an acceptance problem within an Abstract Argumentation Framework (AAF), one can elegantly analyze plausible event interpretations (possibly in an aggregated form), as well as offer explanations for those that conflict with prior process knowledge. Since, in settings where event-to-activity mapping is highly uncertain (or simply under-specified) this reasoning-based approach may yield lowly-informative results and heavy computation, one can think of discovering a sequence-tagging model, trained to suggest highly-probable candidate event interpretations in a context-aware way. However, training such a model optimally may require using a large amount of manually-annotated example traces. Considering the urgent need of developing Green AI solutions enabling environmental and societal sustainability (with reduced labor/computational costs and carbon footprint), we propose a data/computation-efficient neuro-symbolic approach to the problem, where the candidate interpretations returned by the example-driven sequence tagger is refined by the AAF-based reasoner. This allows us to also leverage prior knowledge to compensate for the scarcity of example data, as confirmed by experimental results; clearly, this property is particularly useful in settings where data annotation and model optimization costs are subject to stringent constraints.


Reviews: Bat-G net: Bat-inspired High-Resolution 3D Image Reconstruction using Ultrasonic Echoes

Neural Information Processing Systems

Originality - I think the primary originality of the paper is limited to the engineering set-up specific to obtaining the dataset. It appears quite comprehensive and addresses a number of different geometric patterns that could prove to be a challenge for ultrasound-based image reconstruction. The biomimetic portion of the network also comes across as novel. Although, the specific impact of that portion of the network architecture is not clear. The rest of the paper applies standard supervised learning techniques to a labeled dataset and is not novel.


[Appendix ] Graph Self-supervised Learning with Accurate Discrepancy Learning

Neural Information Processing Systems

Organization In Section A, we first introduce the baselines and our model and then describe the experimental details of graph classification and link prediction tasks but also our in-depth analyses. In this section, we first introduce the computing resources that we use, the baselines, and our model in Section A.1. After that, we describe the experimental setups of the graph classification and link prediction tasks in Section A.2 and Section A.3 as well as the analysis in Section A.4. Computing Resources For all experiments, we use PyTorch and PyTorch Geometric libraries [7, 1], for easy usage of GPU resources. We use TITAN XP and GeForce RTX 2080 Ti for training and evaluating all models. A.1 Baselines and Our Model 1. EdgePred is a predictive learning baseline adopted from the link prediction task of Hamilton et al. [2], whose goal is to predict the existence of edges between the given two nodes.


Graph Self-supervised Learning with Accurate Discrepancy Learning Dongki Kim

Neural Information Processing Systems

Self-supervised learning of graph neural networks (GNNs) aims to learn an accurate representation of the graphs in an unsupervised manner, to obtain transferable representations of them for diverse downstream tasks. Predictive learning and contrastive learning are the two most prevalent approaches for graph self-supervised learning. However, they have their own drawbacks. While the predictive learning methods can learn the contextual relationships between neighboring nodes and edges, they cannot learn global graph-level similarities. Contrastive learning, while it can learn global graph-level similarities, its objective to maximize the similarity between two differently perturbed graphs may result in representations that cannot discriminate two similar graphs with different properties. To tackle such limitations, we propose a framework that aims to learn the exact discrepancy between the original and the perturbed graphs, coined as Discrepancy-based Self-supervised LeArning (D-SLA). Specifically, we create multiple perturbations of the given graph with varying degrees of similarity, and train the model to predict whether each graph is the original graph or the perturbed one. Moreover, we further aim to accurately capture the amount of discrepancy for each perturbed graph using the graph edit distance.


Improving QA Efficiency with DistilBERT: Fine-Tuning and Inference on mobile Intel CPUs

arXiv.org Artificial Intelligence

Question answering (QA) systems have become a cornerstone of natural language processing (NLP), enabling machines to extract precise answers from textual contexts. The Stanford Question Answering Dataset (SQuAD) v1.1 [Rajpurkar et al., 2016] is a widely adopted benchmark for evaluating QA models, comprising over 87,000 training examples of context-question-answer triples. While transformer-based models like BERT [Devlin et al., 2019] have achieved state-of-the-art performance on SQuAD, their computational complexity often demands GPU acceleration, limiting deployment on resource-constrained devices like mid-range CPUs. This study addresses the challenge of developing a transformer-based QA model optimized for inference on a 13th Gen Intel i7-1355U CPU, a 10-core processor with a 5.0 GHz turbo frequency. We focus on DistilBERT [Sanh et al., 2020], a lightweight transformer, to balance performance--measured by F1 score and accuracy--with inference speed. Our contributions include: Comprehensive exploratory data analysis (EDA) of SQuAD v1.1 to inform modeling decisions. Data augmentation strategies to enhance model robustness to low-overlap question-context pairs.


Multi-instance Learning as Downstream Task of Self-Supervised Learning-based Pre-trained Model

arXiv.org Artificial Intelligence

In deep multi-instance learning, the number of applicable instances depends on the data set. In histopathology images, deep learning multi-instance learners usually assume there are hundreds to thousands instances in a bag. However, when the number of instances in a bag increases to 256 in brain hematoma CT, learning becomes extremely difficult. In this paper, we address this drawback. To overcome this problem, we propose using a pre-trained model with self-supervised learning for the multi-instance learner as a downstream task. With this method, even when the original target task suffers from the spurious correlation problem, we show improvements of 5% to 13% in accuracy and 40% to 55% in the F1 measure for the hypodensity marker classification of brain hematoma CT.


Joint-stochastic-approximation Random Fields with Application to Semi-supervised Learning

arXiv.org Machine Learning

Our examination of deep generative models (DGMs) developed for semi-supervised learning (SSL), mainly GANs and VAEs, reveals two problems. First, mode missing and mode covering phenomenons are observed in genertion with GANs and VAEs. Second, there exists an awkward conflict between good classification and good generation in SSL by employing directed generative models. To address these problems, we formally present joint-stochastic-approximation random fields (JRFs) -- a new family of algorithms for building deep undirected generative models, with application to SSL. It is found through synthetic experiments that JRFs work well in balancing mode covering and mode missing, and match the empirical data distribution well. Empirically, JRFs achieve good classification results comparable to the state-of-art methods on widely adopted datasets -- MNIST, SVHN, and CIFAR-10 in SSL, and simultaneously perform good generation.


An Investigation into Whitening Loss for Self-supervised Learning

Neural Information Processing Systems

A desirable objective in self-supervised learning (SSL) is to avoid feature collapse. Whitening loss guarantees collapse avoidance by minimizing the distance between embeddings of positive pairs under the conditioning that the embeddings from different views are whitened. In this paper, we propose a framework with an informative indicator to analyze whitening loss, which provides a clue to demystify several interesting phenomena as well as a pivoting point connecting to other SSL methods. We reveal that batch whitening (BW) based methods do not impose whitening constraints on the embedding, but they only require the embedding to be full-rank. This full-rank constraint is also sufficient to avoid dimensional collapse.


Understanding the Role of Equivariance in Self-supervised Learning

Neural Information Processing Systems

Contrastive learning has been a leading paradigm for self-supervised learning, but it is widely observed that it comes at the price of sacrificing useful features (\eg colors) by being invariant to data augmentations. Given this limitation, there has been a surge of interest in equivariant self-supervised learning (E-SSL) that learns features to be augmentation-aware. However, even for the simplest rotation prediction method, there is a lack of rigorous understanding of why, when, and how E-SSL learns useful features for downstream tasks. To bridge this gap between practice and theory, we establish an information-theoretic perspective to understand the generalization ability of E-SSL. In particular, we identify a critical explaining-away effect in E-SSL that creates a synergy between the equivariant and classification tasks.


Collaboration! Towards Robust Neural Methods for Routing Problems

Neural Information Processing Systems

Despite enjoying desirable efficiency and reduced reliance on domain expertise, existing neural methods for vehicle routing problems (VRPs) suffer from severe robustness issues -- their performance significantly deteriorates on clean instances with crafted perturbations. To enhance robustness, we propose an ensemble-based Collaborative Neural Framework (CNF) w.r.t. the defense of neural VRP methods, which is crucial yet underexplored in the literature. Given a neural VRP method, we adversarially train multiple models in a collaborative manner to synergistically promote robustness against attacks, while boosting standard generalization on clean instances. A neural router is designed to adeptly distribute training instances among models, enhancing overall load balancing and collaborative efficacy. Extensive experiments verify the effectiveness and versatility of CNF in defending against various attacks across different neural VRP methods.