Uncertainty
Towards Guaranteed Safe AI: A Framework for Ensuring Robust and Reliable AI Systems
Dalrymple, David "davidad", Skalse, Joar, Bengio, Yoshua, Russell, Stuart, Tegmark, Max, Seshia, Sanjit, Omohundro, Steve, Szegedy, Christian, Goldhaber, Ben, Ammann, Nora, Abate, Alessandro, Halpern, Joe, Barrett, Clark, Zhao, Ding, Zhi-Xuan, Tan, Wing, Jeannette, Tenenbaum, Joshua
We introduce and define a family of approaches to AI safety, collectively referred to as guaranteed safe (GS) AI. These Ensuring that AI systems reliably and robustly approaches aim to provide high-assurance quantitative guarantees avoid harmful or dangerous behaviours is a crucial about the safety of an AI system's behaviour through challenge, especially for AI systems with a the use of three core components -- a formal safety specification, high degree of autonomy and general intelligence, a world model, and a verifier. We will argue that this or systems used in safety-critical contexts. In strategy is both promising and underexplored, and contrast it this position paper, we will introduce and define with other ongoing efforts in AI safety. We will also outline a family of approaches to AI safety, which we several ongoing avenues of research within the broader GS will refer to as guaranteed safe (GS) AI. The core research agenda, identify some of their core difficulties, and feature of these approaches is that they aim to produce discuss approaches for overcoming these difficulties. Central AI systems which are equipped with highassurance examples of agendas which fall under the GS AI family quantitative safety guarantees. This include Szegedy (2020); Wing (2021); Seshia et al. (2022); is achieved by the interplay of three core components: Russell (2022); Tegmark & Omohundro (2023); 'davidad' a world model (which provides a mathematical Dalrymple (2024); Bengio (2024).
Information limits and Thouless-Anderson-Palmer equations for spiked matrix models with structured noise
Barbier, Jean, Camilli, Francesco, Mondelli, Marco, Xu, Yizhou
We consider a prototypical problem of Bayesian inference for a structured spiked model: a low-rank signal is corrupted by additive noise. While both information-theoretic and algorithmic limits are well understood when the noise is a Gaussian Wigner matrix, the more realistic case of structured noise still proves to be challenging. To capture the structure while maintaining mathematical tractability, a line of work has focused on rotationally invariant noise. However, existing studies either provide sub-optimal algorithms or are limited to special cases of noise ensembles. In this paper, using tools from statistical physics (replica method) and random matrix theory (generalized spherical integrals) we establish the first characterization of the information-theoretic limits for a noise matrix drawn from a general trace ensemble. Remarkably, our analysis unveils the asymptotic equivalence between the rotationally invariant model and a surrogate Gaussian one. Finally, we show how to saturate the predicted statistical limits using an efficient algorithm inspired by the theory of adaptive Thouless-Anderson-Palmer (TAP) equations.
Multi-Fidelity Bayesian Neural Network for Uncertainty Quantification in Transonic Aerodynamic Loads
Vaiuso, Andrea, Immordino, Gabriele, Righi, Marcello, Da Ronch, Andrea
Multi-fidelity models are becoming more prevalent in engineering, particularly in aerospace, as they combine both the computational efficiency of low-fidelity models with the high accuracy of higher-fidelity simulations. Various state-of-the-art techniques exist for fusing data from different fidelity sources, including Co-Kriging and transfer learning in neural networks. This paper aims to implement a multi-fidelity Bayesian neural network model that applies transfer learning to fuse data generated by models at different fidelities. Bayesian neural networks use probability distributions over network weights, enabling them to provide predictions along with estimates of their confidence. This approach harnesses the predictive and data fusion capabilities of neural networks while also quantifying uncertainty. The results demonstrate that the multi-fidelity Bayesian model outperforms the state-of-the-art Co-Kriging in terms of overall accuracy and robustness on unseen data.
Statistical ranking with dynamic covariates
Dong, Pinjun, Han, Ruijian, Jiang, Binyan, Xu, Yiming
We consider a covariate-assisted ranking model grounded in the Plackett--Luce framework. Unlike existing works focusing on pure covariates or individual effects with fixed covariates, our approach integrates individual effects with dynamic covariates. This added flexibility enhances realistic ranking yet poses significant challenges for analyzing the associated estimation procedures. This paper makes an initial attempt to address these challenges. We begin by discussing the sufficient and necessary condition for the model's identifiability. We then introduce an efficient alternating maximization algorithm to compute the maximum likelihood estimator (MLE). Under suitable assumptions on the topology of comparison graphs and dynamic covariates, we establish a quantitative uniform consistency result for the MLE with convergence rates characterized by the asymptotic graph connectivity. The proposed graph topology assumption holds for several popular random graph models under optimal leading-order sparsity conditions. A comprehensive numerical study is conducted to corroborate our theoretical findings and demonstrate the application of the proposed model to real-world datasets, including horse racing and tennis competitions.
Kinetic Interacting Particle Langevin Monte Carlo
Oliva, Paul Felix Valsecchi, Akyildiz, O. Deniz
This paper introduces and analyses interacting underdamped Langevin algorithms, termed Kinetic Interacting Particle Langevin Monte Carlo (KIPLMC) methods, for statistical inference in latent variable models. We propose a diffusion process that evolves jointly in the space of parameters and latent variables and exploit the fact that the stationary distribution of this diffusion concentrates around the maximum marginal likelihood estimate of the parameters. We then provide two explicit discretisations of this diffusion as practical algorithms to estimate parameters of statistical models. For each algorithm, we obtain nonasymptotic rates of convergence for the case where the joint log-likelihood is strongly concave with respect to latent variables and parameters. In particular, we provide convergence analysis for the diffusion together with the discretisation error, providing convergence rate estimates for the algorithms in Wasserstein-2 distance. To demonstrate the utility of the introduced methodology, we provide numerical experiments that demonstrate the effectiveness of the proposed diffusion for statistical inference and the stability of the numerical integrators utilised for discretisation. Our setting covers a broad number of applications, including unsupervised learning, statistical inference, and inverse problems.
Learning Diffusion Priors from Observations by Expectation Maximization
Rozet, François, Andry, Gérôme, Lanusse, François, Louppe, Gilles
Diffusion models recently proved to be remarkable priors for Bayesian inverse problems. However, training these models typically requires access to large amounts of clean data, which could prove difficult in some settings. In this work, we present a novel method based on the expectation-maximization algorithm for training diffusion models from incomplete and noisy observations only. Unlike previous works, our method leads to proper diffusion models, which is crucial for downstream tasks. As part of our method, we propose and motivate a new posterior sampling scheme for unconditional diffusion models.
Sequential Gaussian Variational Inference for Nonlinear State Estimation applied to Robotic Applications
Probabilistic state estimation is essential for robots navigating uncertain environments. Accurately and efficiently managing uncertainty in estimated states is key to robust robotic operation. However, nonlinearities in robotic platforms pose significant challenges that require advanced estimation techniques. Gaussian variational inference (GVI) offers an optimization perspective on the estimation problem, providing analytically tractable solutions and efficiencies derived from the geometry of Gaussian space. We propose a Sequential Gaussian Variational Inference (S-GVI) method to address nonlinearity and provide efficient sequential inference processes. Our approach integrates sequential Bayesian principles into the GVI framework, which are addressed using statistical approximations and gradient updates on the information geometry. Validations through simulations and real-world experiments demonstrate significant improvements in state estimation over the Maximum A Posteriori (MAP) estimation method.
Can Machines Learn the True Probabilities?
When there exists uncertainty, AI machines are The outline of the proof is as follows. After defining some designed to make decisions so as to reach the main concepts, we identify the Success Criterion and the best expected outcomes. Expectations are based necessary condition for any machine to learn the true objective on true facts about the objective environment the probabilities. From these conditions, we derive machines interact with, and those facts can be the theorem that learning implies the true guarantee of encoded into AI models in the form of true objective well-calibration. Roughly speaking, "truly guaranteed wellcalibration" probability functions.
A Survey of Models for Cognitive Diagnosis: New Developments and Future Directions
Wang, Fei, Gao, Weibo, Liu, Qi, Li, Jiatong, Zhao, Guanhao, Zhang, Zheng, Huang, Zhenya, Zhu, Mengxiao, Wang, Shijin, Tong, Wei, Chen, Enhong
Cognitive diagnosis has been developed for decades as an effective measurement tool to evaluate human cognitive status such as ability level and knowledge mastery. It has been applied to a wide range of fields including education, sport, psychological diagnosis, etc. By providing better awareness of cognitive status, it can serve as the basis for personalized services such as well-designed medical treatment, teaching strategy and vocational training. This paper aims to provide a survey of current models for cognitive diagnosis, with more attention on new developments using machine learning-based methods. By comparing the model structures, parameter estimation algorithms, model evaluation methods and applications, we provide a relatively comprehensive review of the recent trends in cognitive diagnosis models. Further, we discuss future directions that are worthy of exploration. In addition, we release two Python libraries: EduData for easy access to some relevant public datasets we have collected, and EduCDM that implements popular CDMs to facilitate both applications and research purposes.
Your Absorbing Discrete Diffusion Secretly Models the Conditional Distributions of Clean Data
Ou, Jingyang, Nie, Shen, Xue, Kaiwen, Zhu, Fengqi, Sun, Jiacheng, Li, Zhenguo, Li, Chongxuan
Discrete diffusion models with absorbing processes have shown promise in language modeling. The key quantities to be estimated are the ratios between the marginal probabilities of two transitive states at all timesteps, called the concrete score. In this paper, we reveal that the concrete score in absorbing diffusion can be expressed as conditional probabilities of clean data, multiplied by a time-dependent scalar in an analytic form. Motivated by this finding, we propose reparameterized absorbing discrete diffusion (RADD), a dedicated diffusion model without time-condition that characterizes the time-independent conditional probabilities. Besides its simplicity, RADD can reduce the number of function evaluations (NFEs) by caching the output of the time-independent network when the noisy sample remains unchanged in a sampling interval. Empirically, RADD is up to 3.5 times faster while achieving similar performance with the strongest baseline. Built upon the new perspective of conditional distributions, we further unify absorbing discrete diffusion and any-order autoregressive models (AO-ARMs), showing that the upper bound on the negative log-likelihood for the diffusion model can be interpreted as an expected negative log-likelihood for AO-ARMs. Further, our RADD models achieve SOTA performance among diffusion models on 5 zero-shot language modeling benchmarks (measured by perplexity) at the GPT-2 scale. Our code is available at https://github.com/ML-GSAI/RADD.