Goto

Collaborating Authors

 Africa


It's the End of the World (And It's Their Fault)

The Atlantic - Technology

It's late morning on a Monday in March and I am, for reasons I will explain momentarily, in a private bowling alley deep in the bowels of a 65 million mansion in Utah. Jesse Armstrong, the showrunner of HBO's hit series Succession, approaches me, monitor headphones around his neck and a wide grin on his face. "I take it you've seen the news," he says, flashing his phone and what appears to be his X feed in my direction. Everyone had: An hour earlier, my boss Jeffrey Goldberg had published a story revealing that U.S. national-security leaders had accidentally added him to a Signal group chat where they discussed their plans to conduct then-upcoming military strikes in Yemen. "Incredibly fucking depressing," Armstrong said.


On Transferring Transferability: Towards a Theory for Size Generalization

arXiv.org Machine Learning

Many modern learning tasks require models that can take inputs of varying sizes. Consequently, dimension-independent architectures have been proposed for domains where the inputs are graphs, sets, and point clouds. Recent work on graph neural networks has explored whether a model trained on low-dimensional data can transfer its performance to higher-dimensional inputs. We extend this body of work by introducing a general framework for transferability across dimensions. We show that transferability corresponds precisely to continuity in a limit space formed by identifying small problem instances with equivalent large ones. This identification is driven by the data and the learning task. We instantiate our framework on existing architectures, and implement the necessary changes to ensure their transferability. Finally, we provide design principles for designing new transferable models. Numerical experiments support our findings.


Learning Parametric Distributions from Samples and Preferences

arXiv.org Machine Learning

Recent advances in language modeling have underscored the role of preference feedback in enhancing model performance. This paper investigates the conditions under which preference feedback improves parameter estimation in classes of continuous parametric distributions. In our framework, the learner observes pairs of samples from an unknown distribution along with their relative preferences depending on the same unknown parameter. We show that preference-based M-estimators achieve a better asymptotic variance than sample-only M-estimators, further improved by deterministic preferences. Leveraging the hard constraints revealed by deterministic preferences, we propose an estimator achieving an estimation error scaling of $\mathcal{O}(1/n)$ -- a significant improvement over the $ฮ˜(1/\sqrt{n})$ rate attainable with samples alone. Next, we establish a lower bound that matches this accelerated rate; up to dimension and problem-dependent constants. While the assumptions underpinning our analysis are restrictive, they are satisfied by notable cases such as Gaussian or Laplace distributions for preferences based on the log-probability reward.


Revisit CP Tensor Decomposition: Statistical Optimality and Fast Convergence

arXiv.org Machine Learning

Canonical Polyadic (CP) tensor decomposition is a fundamental technique for analyzing high-dimensional tensor data. While the Alternating Least Squares (ALS) algorithm is widely used for computing CP decomposition due to its simplicity and empirical success, its theoretical foundation, particularly regarding statistical optimality and convergence behavior, remain underdeveloped, especially in noisy, non-orthogonal, and higher-rank settings. In this work, we revisit CP tensor decomposition from a statistical perspective and provide a comprehensive theoretical analysis of ALS under a signal-plus-noise model. We establish non-asymptotic, minimax-optimal error bounds for tensors of general order, dimensions, and rank, assuming suitable initialization. To enable such initialization, we propose Tucker-based Approximation with Simultaneous Diagonalization (TASD), a robust method that improves stability and accuracy in noisy regimes. Combined with ALS, TASD yields a statistically consistent estimator. We further analyze the convergence dynamics of ALS, identifying a two-phase pattern-initial quadratic convergence followed by linear refinement. We further show that in the rank-one setting, ALS with an appropriately chosen initialization attains optimal error within just one or two iterations.


Generating Diverse Training Samples for Relation Extraction with Large Language Models

arXiv.org Artificial Intelligence

Using Large Language Models (LLMs) to generate training data can potentially be a preferable way to improve zero or few-shot NLP tasks. However, many problems remain to be investigated for this direction. For the task of Relation Extraction (RE), we find that samples generated by directly prompting LLMs may easily have high structural similarities with each other. They tend to use a limited variety of phrasing while expressing the relation between a pair of entities. Therefore, in this paper, we study how to effectively improve the diversity of the training samples generated with LLMs for RE, while also maintaining their correctness. We first try to make the LLMs produce dissimilar samples by directly giving instructions in In-Context Learning (ICL) prompts. Then, we propose an approach to fine-tune LLMs for diversity training sample generation through Direct Preference Optimization (DPO). Our experiments on commonly used RE datasets show that both attempts can improve the quality of the generated training data. We also find that comparing with directly performing RE with an LLM, training a non-LLM RE model with its generated samples may lead to better performance.


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.


Localized Weather Prediction Using Kolmogorov-Arnold Network-Based Models and Deep RNNs

arXiv.org Artificial Intelligence

Weather forecasting is crucial for managing risks and economic planning, particularly in tropical Africa, where extreme events severely impact livelihoods. Yet, existing forecasting methods often struggle with the region's complex, non-linear weather patterns. This study benchmarks deep recurrent neural networks such as $\texttt{LSTM, GRU, BiLSTM, BiGRU}$, and Kolmogorov-Arnold-based models $(\texttt{KAN} and \texttt{TKAN})$ for daily forecasting of temperature, precipitation, and pressure in two tropical cities: Abidjan, Cote d'Ivoire (Ivory Coast) and Kigali (Rwanda). We further introduce two customized variants of $ \texttt{TKAN}$ that replace its original $\texttt{SiLU}$ activation function with $ \texttt{GeLU}$ and \texttt{MiSH}, respectively. Using station-level meteorological data spanning from 2010 to 2024, we evaluate all the models on standard regression metrics. $\texttt{KAN}$ achieves temperature prediction ($R^2=0.9986$ in Abidjan, $0.9998$ in Kigali, $\texttt{MSE} < 0.0014~^\circ C ^2$), while $\texttt{TKAN}$ variants minimize absolute errors for precipitation forecasting in low-rainfall regimes. The customized $\texttt{TKAN}$ models demonstrate improvements over the standard $\texttt{TKAN}$ across both datasets. Classical \texttt{RNNs} remain highly competitive for atmospheric pressure ($R^2 \approx 0.83{-}0.86$), outperforming $\texttt{KAN}$-based models in this task. These results highlight the potential of spline-based neural architectures for efficient and data-efficient forecasting.


VME: A Satellite Imagery Dataset and Benchmark for Detecting Vehicles in the Middle East and Beyond

arXiv.org Artificial Intelligence

Detecting vehicles in satellite images is crucial for traffic management, urban planning, and disaster response. However, current models struggle with real-world diversity, particularly across different regions. This challenge is amplified by geographic bias in existing datasets, which often focus on specific areas and overlook regions like the Middle East. To address this gap, we present the Vehicles in the Middle East (VME) dataset, designed explicitly for vehicle detection in high-resolution satellite images from Middle Eastern countries. Sourced from Maxar, the VME dataset spans 54 cities across 12 countries, comprising over 4,000 image tiles and more than 100,000 vehicles, annotated using both manual and semi-automated methods. Additionally, we introduce the largest benchmark dataset for Car Detection in Satellite Imagery (CDSI), combining images from multiple sources to enhance global car detection. Our experiments demonstrate that models trained on existing datasets perform poorly on Middle Eastern images, while the VME dataset significantly improves detection accuracy in this region. Moreover, state-of-the-art models trained on CDSI achieve substantial improvements in global car detection.


Hawley urges DOJ probe of Chinese trucking company

FOX News

Sen. Josh Hawley, R-Mo., commends President Donald Trump tearing into America's nation builders in the Middle East and weighs in on a Wisconsin judge being indicted for hiding an illegal immigrant from ICE on'The Ingraham Angle.' FIRST ON FOX โ€“ Sen. Josh Hawley, R-Mo., asked the Justice Department on Thursday to investigate a Chinese-owned self-driving trucking company, one of the largest in the U.S., citing allegations that it had shared proprietary data and other sensitive technology with state-linked entities in Beijing. The letter, sent to U.S. Attorney General Pam Bondi and previewed exclusively to Fox News Digital, asks the Justice Department to open a formal investigation into the autonomous truck company TuSimple Holdings, a Chinese-owned company and one of the largest self-driving truck companies in the U.S. In it, Hawley cites recent reporting from the Wall Street Journal that alleges that TuSimple "systematically shared proprietary data, source code, and autonomous driving technologies" with Chinese state-linked entities-- what he described as "blatant disregard" of the 2022 national security agreement with the Committee on Foreign Investment in the United States, or CFIUS. "These reports also revealed communications from TuSimple personnel inside China requesting the shipment of sensitive Nvidia AI chips and detailed records showing'deep and longstanding ties' with Chinese military-affiliated manufacturers," Hawley said. Sen. Josh Hawley, R-Mo., wants the Justice Department to investigate TuSimple Holdings, a Chinese-owned self-driving trucking company. He noted that to date, TuSimple "has not faced serious consequences" for sharing American intellectual property with China, despite having continued to share data with China after signing a national security agreement with the U.S. government in 2022, which was enforced by the Committee on Foreign Investment in the U.S. "If the reports about TuSimple are accurate, they represent not just a violation of export law, but a breach of national trust and a direct threat to American technological leadership," Hawley said.


Tech shares climb after strong Nvidia results despite warning over rise of Chinese rivals

The Guardian

Technology shares climbed on Thursday, buoyed by strong results from Nvidia, despite the AI chip company's boss issuing a warning about the rise of Chinese rivals. The Stoxx Europe tech index rose by 0.8% on Thursday following Nvidia's financial report, with the Dutch semiconductor equipment maker ASML rallying by 2.4%. In the US, futures for the tech-focused Nasdaq climbed 2%, and shares in Nvidia itself jumped 6% in pre-market trading. The boost to tech and artificial intelligence stocks came hours after Nvidia beat Wall Street forecasts, with quarterly revenues jumping 69% to 44bn ( 32.6bn). The company also said it expected deals in the Middle East to start to fill a gap left by the loss of Chinese business.