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AutoSciDACT: Automated Scientific Discovery through Contrastive Embedding and Hypothesis Testing

arXiv.org Machine Learning

Novelty detection in large scientific datasets faces two key challenges: the noisy and high-dimensional nature of experimental data, and the necessity of making statistically robust statements about any observed outliers. While there is a wealth of literature on anomaly detection via dimensionality reduction, most methods do not produce outputs compatible with quantifiable claims of scientific discovery. In this work we directly address these challenges, presenting the first step towards a unified pipeline for novelty detection adapted for the rigorous statistical demands of science. We introduce AutoSciDACT (Automated Scientific Discovery with Anomalous Contrastive Testing), a general-purpose pipeline for detecting novelty in scientific data. AutoSciDACT begins by creating expressive low-dimensional data representations using a contrastive pre-training, leveraging the abundance of high-quality simulated data in many scientific domains alongside expertise that can guide principled data augmentation strategies. These compact embeddings then enable an extremely sensitive machine learning-based two-sample test using the New Physics Learning Machine (NPLM) framework, which identifies and statistically quantifies deviations in observed data relative to a reference distribution (null hypothesis). We perform experiments across a range of astronomical, physical, biological, image, and synthetic datasets, demonstrating strong sensitivity to small injections of anomalous data across all domains.


Bridging Prediction and Attribution: Identifying Forward and Backward Causal Influence Ranges Using Assimilative Causal Inference

arXiv.org Machine Learning

Causal inference identifies cause-and-effect relationships between variables. While traditional approaches rely on data to reveal causal links, a recently developed method, assimilative causal inference (ACI), integrates observations with dynamical models. It utilizes Bayesian data assimilation to trace causes back from observed effects by quantifying the reduction in uncertainty. ACI advances the detection of instantaneous causal relationships and the intermittent reversal of causal roles over time. Beyond identifying causal connections, an equally important challenge is determining the associated causal influence range (CIR), indicating when causal influences emerged and for how long they persist. In this paper, ACI is employed to develop mathematically rigorous formulations of both forward and backward CIRs at each time. The forward CIR quantifies the temporal impact of a cause, while the backward CIR traces the onset of triggers for an observed effect, thus characterizing causal predictability and attribution of outcomes at each transient phase, respectively. Objective and robust metrics for both CIRs are introduced, eliminating the need for empirical thresholds. Computationally efficient approximation algorithms to compute CIRs are developed, which facilitate the use of closed-form expressions for a broad class of nonlinear dynamical systems. Numerical simulations demonstrate how this forward and backward CIR framework provides new possibilities for probing complex dynamical systems. It advances the study of bifurcation-driven and noise-induced tipping points in Earth systems, investigates the impact from resolving the interfering variables when determining the influence ranges, and elucidates atmospheric blocking mechanisms in the equatorial region. These results have direct implications for science, policy, and decision-making.


Adapting to Stochastic and Adversarial Losses in Episodic MDPs with Aggregate Bandit Feedback

arXiv.org Machine Learning

We study online learning in finite-horizon episodic Markov decision processes (MDPs) under the challenging aggregate bandit feedback model, where the learner observes only the cumulative loss incurred in each episode, rather than individual losses at each state-action pair. While prior work in this setting has focused exclusively on worst-case analysis, we initiate the study of best-of-both-worlds (BOBW) algorithms that achieve low regret in both stochastic and adversarial environments. We propose the first BOBW algorithms for episodic tabular MDPs with aggregate bandit feedback. In the case of known transitions, our algorithms achieve $O(\log T)$ regret in stochastic settings and ${O}(\sqrt{T})$ regret in adversarial ones. Importantly, we also establish matching lower bounds, showing the optimality of our algorithms in this setting. We further extend our approach to unknown-transition settings by incorporating confidence-based techniques. Our results rely on a combination of FTRL over occupancy measures, self-bounding techniques, and new loss estimators inspired by recent advances in online shortest path problems. Along the way, we also provide the first individual-gap-dependent lower bounds and demonstrate near-optimal BOBW algorithms for shortest path problems with bandit feedback.


Incomplete Multi-view Clustering via Hierarchical Semantic Alignment and Cooperative Completion

arXiv.org Machine Learning

Incomplete multi-view data, where certain views are entirely missing for some samples, poses significant challenges for traditional multi-view clustering methods. Existing deep incomplete multi-view clustering approaches often rely on static fusion strategies or two-stage pipelines, leading to suboptimal fusion results and error propagation issues. To address these limitations, this paper proposes a novel incomplete multi-view clustering framework based on Hierarchical Semantic Alignment and Cooperative Completion (HSACC). HSACC achieves robust cross-view fusion through a dual-level semantic space design. In the low-level semantic space, consistency alignment is ensured by maximizing mutual information across views. In the high-level semantic space, adaptive view weights are dynamically assigned based on the distributional affinity between individual views and an initial fused representation, followed by weighted fusion to generate a unified global representation. Additionally, HSACC implicitly recovers missing views by projecting aligned latent representations into high-dimensional semantic spaces and jointly optimizes reconstruction and clustering objectives, enabling cooperative learning of completion and clustering. Experimental results demonstrate that HSACC significantly outperforms state-of-the-art methods on five benchmark datasets. Ablation studies validate the effectiveness of the hierarchical alignment and dynamic weighting mechanisms, while parameter analysis confirms the model's robustness to hyperparameter variations.


ChatGPT shares data on how many users exhibit psychosis or suicidal thoughts

BBC News

OpenAI has released new estimates of the number of ChatGPT users who exhibit possible signs of mental health emergencies, including mania, psychosis or suicidal thoughts. The company said that around 0.07% of ChatGPT users active in a given week exhibited such signs, adding that its artificial intelligence (AI) chatbot recognizes and responds to these sensitive conversations. While OpenAI maintains these cases are extremely rare, critics said even a small percentage may amount to hundreds of thousands of people, as ChatGPT recently reached 800 million weekly active users, per boss Sam Altman. As scrutiny mounts, the company said it built a network of experts around the world to advise it. Those experts include more than 170 psychiatrists, psychologists, and primary care physicians who have practiced in 60 countries, the company said. They have devised a series of responses in ChatGPT to encourage users to seek help in the real world, according to OpenAI.


Hamas hands over remains of captive as Israeli drone strike kills two

Al Jazeera

Can Israel annex the West Bank if the US says no? Will the US plan for Gaza fail? 'We survived the war, we may not survive the ceasefire' Who are the 95 healthcare workers held by Israel? Hamas has handed over the remains of another dead captive to Israel, hours after an Israeli drone attack in southern Gaza killed two Palestinians amid a fragile ceasefire. The Israeli military said on Monday that the Red Cross had taken custody of the coffin and was in the process of transporting it to the army's troops in Gaza. The remains of 16 had been handed over as of Monday.


UN slams Israel after attack on peacekeepers in Lebanon

Al Jazeera

Can Israel annex the West Bank if the US says no? Will the US plan for Gaza fail? 'We survived the war, we may not survive the ceasefire' Who are the 95 healthcare workers held by Israel? The United Nations and France have condemned an Israeli attack that hit UN peacekeeping troops in southern Lebanon. UN spokesperson Stephane Dujarric said on Monday that the previous day's attack on UNIFIL troops, which he said involved an Israeli drone dropping a grenade in the vicinity of a patrol, as well as a tank opening fire on peacekeepers near the border town of Kfar Kila, was "very, very dangerous". Israel has violated the truce on a near-daily basis.


More than a million people every week show suicidal intent when chatting with ChatGPT, OpenAI estimates

The Guardian

OpenAI claimed that its recent GPT-5 update improved user safety in a model evaluation involving more than 1,000 self-harm and suicide conversations. OpenAI claimed that its recent GPT-5 update improved user safety in a model evaluation involving more than 1,000 self-harm and suicide conversations. More than a million ChatGPT users each week send messages that include "explicit indicators of potential suicidal planning or intent", according to a blogpost published by OpenAI on Monday. The finding, part of an update on how the chatbot handles sensitive conversations, is one of the most direct statements from the artificial intelligence giant on the scale of how AI can exacerbate mental health issues. In addition to its estimates on suicidal ideations and related interactions, OpenAI also said that about 0.07% of users active in a given week - about 560,000 of its touted 800m weekly users - show "possible signs of mental health emergencies related to psychosis or mania".


Tesla revives 'Mad Max' mode in Full Self-Driving

FOX News

Tesla brings back Mad Max mode in its Full Self-Driving system update, allowing more aggressive driving amid ongoing regulatory investigations.


The All-Clad Pizza Oven Is 800 Off Right Now

WIRED

The All-Clad pizza oven was one of my biggest surprises of the summer. All products featured on WIRED are independently selected by our editors. However, we may receive compensation from retailers and/or from purchases of products through these links. Cookware brand All-Clad surprised me this year. This summer, it breezed into the backyard pizza world with a debut pizza oven that I like as well as any oven I've tested this year.