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Random Forest Kernel for High-Dimension Low Sample Size Classification

arXiv.org Machine Learning

High dimension, low sample size (HDLSS) problems are numerous among real-world applications of machine learning. From medical images to text processing, traditional machine learning algorithms are usually unsuccessful in learning the best possible concept from such data. In a previous work, we proposed a dissimilarity-based approach for multi-view classification, the Random Forest Dissimilarity (RFD), that perfoms state-of-the-art results for such problems. In this work, we transpose the core principle of this approach to solving HDLSS classification problems, by using the RF similarity measure as a learned precomputed SVM kernel (RFSVM). We show that such a learned similarity measure is particularly suited and accurate for this classification context. Experiments conducted on 40 public HDLSS classification datasets, supported by rigorous statistical analyses, show that the RFSVM method outperforms existing methods for the majority of HDLSS problems and remains at the same time very competitive for low or non-HDLSS problems.


Microsoft's Copilot AI is officially coming to Windows 10

Engadget

Microsoft's AI ambitions are moving a bit backwards: Today, the company has confirmed that it's bringing Copilot AI to Windows 10. At first, it'll be available to Windows Insider users in an upcoming Release Preview update, where Copilot will appear on the right side of the Task Bar. Once selected, you'll see the familiar Copilot interface, which you can use to ask the AI questions, manage Windows features or interact with documents. Microsoft says the Copilot window won't overlap with desktop content or block open windows. If this all sounds familiar, it's because Windows Central reported that Windows 10 would be getting Copilot earlier this month.


Efficient End-to-End Visual Document Understanding with Rationale Distillation

arXiv.org Artificial Intelligence

Understanding visually situated language requires recognizing text and visual elements, and interpreting complex layouts. State-of-the-art methods commonly use specialized pre-processing tools, such as optical character recognition (OCR) systems, that map document image inputs to extracted information in the space of textual tokens, and sometimes also employ large language models (LLMs) to reason in text token space. However, the gains from external tools and LLMs come at the cost of increased computational and engineering complexity. In this paper, we ask whether small pretrained image-to-text models can learn selective text or layout recognition and reasoning as an intermediate inference step in an end-to-end model for pixel-level visual language understanding. We incorporate the outputs of such OCR tools, LLMs, and larger multimodal models as intermediate ``rationales'' on training data, and train a small student model to predict both rationales and answers for input questions based on those training examples. A student model based on Pix2Struct (282M parameters) achieves consistent improvements on three visual document understanding benchmarks representing infographics, scanned documents, and figures, with improvements of more than 4\% absolute over a comparable Pix2Struct model that predicts answers directly.


Information-Theoretic Bounds on The Removal of Attribute-Specific Bias From Neural Networks

arXiv.org Artificial Intelligence

Ensuring a neural network is not relying on protected attributes (e.g., race, sex, age) for predictions is crucial in advancing fair and trustworthy AI. While several promising methods for removing attribute bias in neural networks have been proposed, their limitations remain under-explored. In this work, we mathematically and empirically reveal an important limitation of attribute bias removal methods in presence of strong bias. Specifically, we derive a general non-vacuous information-theoretical upper bound on the performance of any attribute bias removal method in terms of the bias strength. We provide extensive experiments on synthetic, image, and census datasets to verify the theoretical bound and its consequences in practice. Our findings show that existing attribute bias removal methods are effective only when the inherent bias in the dataset is relatively weak, thus cautioning against the use of these methods in smaller datasets where strong attribute bias can occur, and advocating the need for methods that can overcome this limitation.


Formal Verification of Long Short-Term Memory based Audio Classifiers: A Star based Approach

arXiv.org Artificial Intelligence

Deep Neural Networks (DNNs) have demonstrated remarkable capabilities in addressing intricate tasks like image classification, object detection, speech recognition, natural language processing, and document analysis, at times even surpassing human performance [21,23,24]. This success has ignited a surge in exploring the viability of DNNs across diverse real-world domains, including biometric authentication, mobile facial recognition for security, and malware detection. However, given the sensitive nature of the data in these critical applications, incorporating safety, security, and robust verification into their design has become paramount. However, studies have revealed that even slight modifications in input data can effectively mislead cutting-edge, well-trained networks, causing inaccuracies in their predictions [12, 32, 40]. The arena of network verification has primarily concentrated on image inputs, particularly emphasizing the assurance of safety and robustness in various classification neural networks [2, 7, 19, 31, 43, 44]. Previous investigations have scrutinized a range of network architectures, encompassing feed-forward neural networks (FFNNs [42]), convolutional neural networks (CNNs [44]), semantic segmentation networks (SSNs [43]), and a few using Recurrent Neural Networks (RNNs [41]) employing diverse set-based reachability tools such as Neural Network Verification (NNV [26,45]) and JuliaReach [6], among others. Models utilizing NNs for audio classification have found application in diverse tasks, ranging from Music Genre Classification [8, 10, 11] and Environmental Sound Classification [4, 9, 13] to Audio Generation [33, 36]. Therefore, formal verification of audio classification systems holds paramount importance in ensuring their reliability and safety, particularly in safety-critical applications such as autonomous vehicles [35, 46], medical diagnosis [15, 30], and industrial monitoring [47]. This study introduces an extension, building upon the foundations laid by two recent studies [34,41] in the domain of formal verification.


Text Sanitization Beyond Specific Domains: Zero-Shot Redaction & Substitution with Large Language Models

arXiv.org Artificial Intelligence

In the context of information systems, text sanitization techniques are used to identify and remove sensitive data to comply with security and regulatory requirements. Even though many methods for privacy preservation have been proposed, most of them are focused on the detection of entities from specific domains (e.g., credit card numbers, social security numbers), lacking generality and requiring customization for each desirable domain. Moreover, removing words is, in general, a drastic measure, as it can degrade text coherence and contextual information. Less severe measures include substituting a word for a safe alternative, yet it can be challenging to automatically find meaningful substitutions. We present a zero-shot text sanitization technique that detects and substitutes potentially sensitive information using Large Language Models. Our evaluation shows that our method excels at protecting privacy while maintaining text coherence and contextual information, preserving data utility for downstream tasks.


JWSign: A Highly Multilingual Corpus of Bible Translations for more Diversity in Sign Language Processing

arXiv.org Artificial Intelligence

Advancements in sign language processing have been hindered by a lack of sufficient data, impeding progress in recognition, translation, and production tasks. The absence of comprehensive sign language datasets across the world's sign languages has widened the gap in this field, resulting in a few sign languages being studied more than others, making this research area extremely skewed mostly towards sign languages from high-income countries. In this work we introduce a new large and highly multilingual dataset for sign language translation: JWSign. The dataset consists of 2,530 hours of Bible translations in 98 sign languages, featuring more than 1,500 individual signers. On this dataset, we report neural machine translation experiments. Apart from bilingual baseline systems, we also train multilingual systems, including some that take into account the typological relatedness of signed or spoken languages. Our experiments highlight that multilingual systems are superior to bilingual baselines, and that in higher-resource scenarios, clustering language pairs that are related improves translation quality.


K-space Cold Diffusion: Learning to Reconstruct Accelerated MRI without Noise

arXiv.org Artificial Intelligence

Deep learning-based MRI reconstruction models have achieved superior performance these days. Most recently, diffusion models have shown remarkable performance in image generation, in-painting, super-resolution, image editing and more. As a generalized diffusion model, cold diffusion further broadens the scope and considers models built around arbitrary image transformations such as blurring, down-sampling, etc. In this paper, we propose a k-space cold diffusion model that performs image degradation and restoration in k-space without the need for Gaussian noise. We provide comparisons with multiple deep learning-based MRI reconstruction models and perform tests on a well-known large open-source MRI dataset. Our results show that this novel way of performing degradation can generate high-quality reconstruction images for accelerated MRI.


Towards more Practical Threat Models in Artificial Intelligence Security

arXiv.org Artificial Intelligence

Recent works have identified a gap between research and practice in artificial intelligence security: threats studied in academia do not always reflect the practical use and security risks of AI. For example, while models are often studied in isolation, they form part of larger ML pipelines in practice. Recent works also brought forward that adversarial manipulations introduced by academic attacks are impractical. We take a first step towards describing the full extent of this disparity. To this end, we revisit the threat models of the six most studied attacks in AI security research and match them to AI usage in practice via a survey with \textbf{271} industrial practitioners. On the one hand, we find that all existing threat models are indeed applicable. On the other hand, there are significant mismatches: research is often too generous with the attacker, assuming access to information not frequently available in real-world settings. Our paper is thus a call for action to study more practical threat models in artificial intelligence security.


An Attention-Based Denoising Framework for Personality Detection in Social Media Texts

arXiv.org Artificial Intelligence

In social media networks, users produce a large amount of text content anytime, providing researchers with a valuable approach to digging for personality-related information. Personality detection based on user-generated texts is a universal method that can be used to build user portraits. The presence of noise in social media texts hinders personality detection. However, previous studies have not fully addressed this challenge. Inspired by the scanning reading technique, we propose an attention-based information extraction mechanism (AIEM) for long texts, which is applied to quickly locate valuable pieces of information, and focus more attention on the deep semantics of key pieces. Then, we provide a novel attention-based denoising framework (ADF) for personality detection tasks and achieve state-of-the-art performance on two commonly used datasets. Notably, we obtain an average accuracy improvement of 10.2% on the gold standard Twitter-Myers-Briggs Type Indicator (Twitter-MBTI) dataset. We made our code publicly available on GitHub. We shed light on how AIEM works to magnify personality-related signals.