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Reasoning Beyond Labels: Measuring LLM Sentiment in Low-Resource, Culturally Nuanced Contexts

arXiv.org Artificial Intelligence

Sentiment analysis in low-resource, culturally nuanced contexts challenges conventional NLP approaches that assume fixed labels and universal affective expressions. We present a diagnostic framework that treats sentiment as a context-dependent, culturally embedded construct, and evaluate how large language models (LLMs) reason about sentiment in informal, code-mixed WhatsApp messages from Nairobi youth health groups. Using a combination of human-annotated data, sentiment-flipped counterfactuals, and rubric-based explanation evaluation, we probe LLM interpretability, robustness, and alignment with human reasoning. Framing our evaluation through a social-science measurement lens, we operationalize and interrogate LLMs outputs as an instrument for measuring the abstract concept of sentiment. Our findings reveal significant variation in model reasoning quality, with top-tier LLMs demonstrating interpretive stability, while open models often falter under ambiguity or sentiment shifts. This work highlights the need for culturally sensitive, reasoning-aware AI evaluation in complex, real-world communication.


OpenAI Announces Massive US Government Partnership

WIRED

OpenAI is partnering with the US government to make its leading frontier models available to federal employees. Under the agreement, federal agencies can access OpenAI's models for 1 for the next year, per a Wednesday announcement from the company and the General Services Administration (GSA). The partnership is the culmination of months of effort on the part of OpenAI CEO Sam Altman and other OpenAI executives, who have been cozying up to the Trump administration since before President Donald Trump retook the White House in January. Since at least May of this year, high-ranking OpenAI employees have been meeting with the GSA and other government agencies, such as the Food and Drug Administration, to promote the company's tools, according to documents obtained by WIRED. On July 23, OpenAI chief operating officer Brad Lightcap and other OpenAI executives were invited to a private after-party hosted by the Hill and Valley Forum in Washington, DC.


Learning quadratic neural networks in high dimensions: SGD dynamics and scaling laws

arXiv.org Machine Learning

We study the optimization and sample complexity of gradient-based training of a two-layer neural network with quadratic activation function in the high-dimensional regime, where the data is generated as $y \propto \sum_{j=1}^{r}λ_j σ\left(\langle \boldsymbol{θ_j}, \boldsymbol{x}\rangle\right), \boldsymbol{x} \sim N(0,\boldsymbol{I}_d)$, $σ$ is the 2nd Hermite polynomial, and $\lbrace\boldsymbolθ_j \rbrace_{j=1}^{r} \subset \mathbb{R}^d$ are orthonormal signal directions. We consider the extensive-width regime $r \asymp d^β$ for $β\in [0, 1)$, and assume a power-law decay on the (non-negative) second-layer coefficients $λ_j\asymp j^{-α}$ for $α\geq 0$. We present a sharp analysis of the SGD dynamics in the feature learning regime, for both the population limit and the finite-sample (online) discretization, and derive scaling laws for the prediction risk that highlight the power-law dependencies on the optimization time, sample size, and model width. Our analysis combines a precise characterization of the associated matrix Riccati differential equation with novel matrix monotonicity arguments to establish convergence guarantees for the infinite-dimensional effective dynamics.


VQA support to Arabic Language Learning Educational Tool

arXiv.org Artificial Intelligence

--W e address the problem of scarcity of educational Arabic Language Learning tools that advocates modern pedagogical models such active learning which ensures language proficiency . In fact, we investigate the design and evaluation of an AI-powered educational tool designed to enhance Arabic language learning for non-native speakers with beginner-to-intermediate proficiency level. The tool leverages advanced AI models to generate interactive visual quizzes, deploying Visual Question Answering as the primary activity . Adopting a constructivist learning approach, the system encourages active learning through real-life visual quizzes, and image-based questions that focus on improving vocabulary, grammar, and comprehension. The system integrates Vision-Language Pretraining models to generate contextually relevant image description from which Large Language Model generate assignments based on customized Arabic language Learning quizzes thanks to prompting. The effectiveness of the tool is evaluated through a manual annotated benchmark consisting of 1266 real-life visual quizzes, with human participants providing feedback. The results show a suitable accuracy rates, validating the tool's potential to bridge the gap in Arabic language education and highlighting the tool's promise as a reliable, AI-powered resource for Arabic learners, offering personalized and interactive learning experiences. I. Introduction Language learning has never been more important than it is today. Since the onset of globalization, language learning has become essential in facilitating communication across cultures and opening up numerous educational and professional opportunities [6]. To excel in any language, it is crucial to develop proficiency in all four core skills: listening, writing, reading, and speaking.


Data Overdose? Time for a Quadruple Shot: Knowledge Graph Construction using Enhanced Triple Extraction

arXiv.org Artificial Intelligence

The rapid expansion of publicly-available medical data presents a challenge for clinicians and researchers alike, increasing the gap between the volume of scientific literature and its applications. The steady growth of studies and findings overwhelms medical professionals at large, hindering their ability to systematically review and understand the latest knowledge. This paper presents an approach to information extraction and automatic knowledge graph (KG) generation to identify and connect biomedical knowledge. Through a pipeline of large language model (LLM) agents, the system decomposes 44 PubMed abstracts into semantically meaningful proposition sentences and extracts KG triples from these sentences. The triples are enhanced using a combination of open domain and ontology-based information extraction methodologies to incorporate ontological categories. On top of this, a context variable is included during extraction to allow the triple to stand on its own - thereby becoming `quadruples'. The extraction accuracy of the LLM is validated by comparing natural language sentences generated from the enhanced triples to the original propositions, achieving an average cosine similarity of 0.874. The similarity for generated sentences of enhanced triples were compared with generated sentences of ordinary triples showing an increase as a result of the context variable. Furthermore, this research explores the ability for LLMs to infer new relationships and connect clusters in the knowledge base of the knowledge graph. This approach leads the way to provide medical practitioners with a centralised, updated in real-time, and sustainable knowledge source, and may be the foundation of similar gains in a wide variety of fields.


DeepGB-TB: A Risk-Balanced Cross-Attention Gradient-Boosted Convolutional Network for Rapid, Interpretable Tuberculosis Screening

arXiv.org Artificial Intelligence

Large-scale tuberculosis (TB) screening is limited by the high cost and operational complexity of traditional diagnostics, creating a need for artificial-intelligence solutions. We propose DeepGB-TB, a non-invasive system that instantly assigns TB risk scores using only cough audio and basic demographic data. The model couples a lightweight one-dimensional convolutional neural network for audio processing with a gradient-boosted decision tree for tabular features. Its principal innovation is a Cross-Modal Bidirectional Cross-Attention module (CM-BCA) that iteratively exchanges salient cues between modalities, emulating the way clinicians integrate symptoms and risk factors. To meet the clinical priority of minimizing missed cases, we design a Tuberculosis Risk-Balanced Loss (TRBL) that places stronger penalties on false-negative predictions, thereby reducing high-risk misclassifications. DeepGB-TB is evaluated on a diverse dataset of 1,105 patients collected across seven countries, achieving an AUROC of 0.903 and an F1-score of 0.851, representing a new state of the art. Its computational efficiency enables real-time, offline inference directly on common mobile devices, making it ideal for low-resource settings. Importantly, the system produces clinically validated explanations that promote trust and adoption by frontline health workers. By coupling AI innovation with public-health requirements for speed, affordability, and reliability, DeepGB-TB offers a tool for advancing global TB control.


The Much-Hyped New em Wizard of Oz /em Is an Atrocity

Slate

Although it is, at least according to the Library of Congress, the most-watched movie of all time, The Wizard of Oz was a costly failure at the box office, and only became a perennial favorite thanks to the regular TV airings that began in the 1950s. But in the decades since it's become a metonym for the wonder of the big screen, a movie even people who prefer their content streaming will make the effort to see in a movie theater. Beginning on Labor Day weekend, audiences will get to experience the movie on perhaps the largest screen ever created. But it won't be The Wizard of Oz as we've come to know it for the better part of a century. The version of the movie that will fill Las Vegas' Sphere starting Aug. 28 has been retooled to fit the venue's curved shell, its images enhanced and expanded to fill four football fields' worth of 16K LED screens--the foundation of an immersive presentation that also includes flames, gusts of wind, and inflatable flying monkeys piloted by drone. It is, to quote the title of a CBS news report, "The Wizard of Oz as you've never seen it before."


He'd need some LARGE SquarePants: Footage of a sea star with a 'big bottom' sparks hilarity as it's compared to SpongeBob's Patrick

Daily Mail - Science & tech

The sea floor is home to all sorts of weird and wonderful creatures. But one in particular has become an online sensation, thanks to its impressive'buttocks'. A big–bottomed sea star has been spotted more than 1,000 metres (3,280ft) below the waves. And it appears to have a backside that will make even the most avid gymgoer jealous. This has led many baffled viewers to compare the creature to Patrick from the animated series Spongebob Squarepants.


Russia-Ukraine war: List of key events, day 1,258

Al Jazeera

Three people were killed in a Russian attack on the Stepnohirsk community in Ukraine's Zaporizhia region, the local military administration said on Telegram. Russia launched 405 attacks on 10 settlements in the region in the past day, the administration said on Monday. Russian drone attacks killed three people in the Chuhuiv district of Ukraine's Kharkiv region, the regional prosecutor's office said. The victims included a man killed when Russian drones caused a fire in his home in the village of Losivka, and a man and a woman who were riding a motorcycle when they were killed. The prosecutor's office said it was investigating the motorcycle attack as a possible war crime.


Debiasing Machine Learning Predictions for Causal Inference Without Additional Ground Truth Data: "One Map, Many Trials" in Satellite-Driven Poverty Analysis

arXiv.org Machine Learning

Machine learning models trained on Earth observation data, such as satellite imagery, have demonstrated significant promise in predicting household-level wealth indices, enabling the creation of high-resolution wealth maps that can be leveraged across multiple causal trials. However, because standard training objectives prioritize overall predictive accuracy, these predictions inherently suffer from shrinkage toward the mean, leading to attenuated estimates of causal treatment effects and limiting their utility in policy. Existing debiasing methods, such as Prediction-Powered Inference, can handle this attenuation bias but require additional fresh ground-truth data at the downstream stage of causal inference, which restricts their applicability in data-scarce environments. Here, we introduce and evaluate two correction methods -- linear calibration correction and Tweedie's correction -- that substantially reduce prediction bias without relying on newly collected labeled data. Linear calibration corrects bias through a straightforward linear transformation derived from held-out calibration data, whereas Tweedie's correction leverages empirical Bayes principles to directly address shrinkage-induced biases by exploiting score functions derived from the model's learning patterns. Through analytical exercises and experiments using Demographic and Health Survey data, we demonstrate that the proposed methods meet or outperform existing approaches that either require (a) adjustments to training pipelines or (b) additional labeled data. These approaches may represent a promising avenue for improving the reliability of causal inference when direct outcome measures are limited or unavailable, enabling a "one map, many trials" paradigm where a single upstream data creation team produces predictions usable by many downstream teams across diverse ML pipelines.