Plotting

 Capital Region


AI can spontaneously develop human-like communication, study finds

The Guardian

Artificial intelligence can spontaneously develop human-like social conventions, a study has found. The research, undertaken in collaboration between City St George's, University of London and the IT University of Copenhagen, suggests that when large language model (LLM) AI agents such as ChatGPT communicate in groups without outside involvement they can begin to adopt linguistic forms and social norms the same way that humans do when they socialise. The study's lead author, Ariel Flint Ashery, a doctoral researcher at City St George's, said the group's work went against the majority of research done into AI, as it treated AI as a social rather than solitary entity. "Most research so far has treated LLMs in isolation but real-world AI systems will increasingly involve many interacting agents," said Ashery. "We wanted to know: can these models coordinate their behaviour by forming conventions, the building blocks of a society? The answer is yes, and what they do together can't be reduced to what they do alone."


Bayesian generative models can flag performance loss, bias, and out-of-distribution image content

arXiv.org Machine Learning

Generative models are popular for medical imaging tasks such as anomaly detection, feature extraction, data visualization, or image generation. Since they are parameterized by deep learning models, they are often sensitive to distribution shifts and unreliable when applied to out-of-distribution data, creating a risk of, e.g. underrepresentation bias. This behavior can be flagged using uncertainty quantification methods for generative models, but their availability remains limited. We propose SLUG: A new UQ method for VAEs that combines recent advances in Laplace approximations with stochastic trace estimators to scale gracefully with image dimensionality. We show that our UQ score -- unlike the VAE's encoder variances -- correlates strongly with reconstruction error and racial underrepresentation bias for dermatological images. We also show how pixel-wise uncertainty can detect out-of-distribution image content such as ink, rulers, and patches, which is known to induce learning shortcuts in predictive models.


Gradients of Functions of Large Matrices

Neural Information Processing Systems

Tuning scientific and probabilistic machine learning models - for example, partial differential equations, Gaussian processes, or Bayesian neural networks - often relies on evaluating functions of matrices whose size grows with the data set or the number of parameters. While the state-of-the-art for evaluating these quantities is almost always based on Lanczos and Arnoldi iterations, the present work is the first to explain how to differentiate these workhorses of numerical linear algebra efficiently. To get there, we derive previously unknown adjoint systems for Lanczos and Arnoldi iterations, implement them in JAX, and show that the resulting code can compete with Diffrax when it comes to differentiating PDEs, GPyTorch for selecting Gaussian process models and beats standard factorisation methods for calibrating Bayesian neural networks. All this is achieved without any problem-specific code optimisation.


Kermut: Composite kernel regression for protein variant effects University of Copenhagen University of Copenhagen Novonesis Lars Olsen Jesper Salomon Wouter Boomsma

Neural Information Processing Systems

Reliable prediction of protein variant effects is crucial for both protein optimization and for advancing biological understanding. For practical use in protein engineering, it is important that we can also provide reliable uncertainty estimates for our predictions, and while prediction accuracy has seen much progress in recent years, uncertainty metrics are rarely reported. We here provide a Gaussian process regression model, Kermut, with a novel composite kernel for modeling mutation similarity, which obtains state-of-the-art performance for supervised protein variant effect prediction while also offering estimates of uncertainty through its posterior. An analysis of the quality of the uncertainty estimates demonstrates that our model provides meaningful levels of overall calibration, but that instance-specific uncertainty calibration remains more challenging.


The Good Robot podcast: Re-imagining voice assistants with Stina Hasse Jรธrgensen and Frederik Juutilainen

AIHub

Hosted by Eleanor Drage and Kerry McInerney, The Good Robot is a podcast which explores the many complex intersections between gender, feminism and technology. To develop voice assistants like Siri and Alexa, companies spend years investigating what sounds like a human voice and what doesn't. But what we've ended up with is just one possibility of the kinds of voices that we could be interacting with. In this episode, we talked to sound engineer Frederik Juutilainen, and assistant professor at the University of Copenhagen, Stina Hasse Jรธrgensen, about their participation in [multi'vocal], an experimental research project that created an alternative voice assistant by asking people at a rock festival in Denmark to speak into a portable recording box. We talk about voice assistants' inability to stutter, lisp and code switch, and whether a voice can express multiple personalities, genders and ages.


Numerically robust Gaussian state estimation with singular observation noise

arXiv.org Artificial Intelligence

This article proposes numerically robust algorithms for Gaussian state estimation with singular observation noise. Our approach combines a series of basis changes with Bayes' rule, transforming the singular estimation problem into a nonsingular one with reduced state dimension. In addition to ensuring low runtime and numerical stability, our proposal facilitates marginal-likelihood computations and Gauss-Markov representations of the posterior process. We analyse the proposed method's computational savings and numerical robustness and validate our findings in a series of simulations.


These two new AI benchmarks could help make models less biased

MIT Technology Review

"When we are focused on treating everybody exactly the same, it can be overly stringent," says Angelina Wang, a postdoc at the Stanford Institute for Human-Centered AI and RegLab, who is the lead author of the paper. "It's forcing people to be treated the same even when there are legitimate differences." Ignoring differences between groups may in fact make AI systems less fair. "Sometimes being able to differentiate between groups is actually useful to treat the people from different groups more fairly," says Isabelle Augenstein, a computer science professor at the University of Copenhagen, who was not involved in the research. Wang and her colleagues created benchmarks to evaluate AI systems along two different dimensions that the team devised: difference awareness and contextual awareness.


These new AI benchmarks could help make models less biased

MIT Technology Review

"When we are focused on treating everybody exactly the same, it can be overly stringent," says Angelina Wang, a postdoc at the Stanford Institute for Human-Centered AI and RegLab, who is the lead author of the paper. "It's forcing people to be treated the same even when there are legitimate differences." Ignoring differences between groups may in fact make AI systems less fair. "Sometimes being able to differentiate between groups is actually useful to treat the people from different groups more fairly," says Isabelle Augenstein, a computer science professor at the University of Copenhagen, who was not involved in the research. Wang and her colleagues created eight new benchmarks to evaluate AI systems along two different dimensions that the team devised: descriptive and normative.


Open-Set Recognition of Novel Species in Biodiversity Monitoring

arXiv.org Artificial Intelligence

Machine learning is increasingly being applied to facilitate long-term, large-scale biodiversity monitoring. With most species on Earth still undiscovered or poorly documented, species-recognition models are expected to encounter new species during deployment. We introduce Open-Insects, a fine-grained image recognition benchmark dataset for open-set recognition and out-of-distribution detection in biodiversity monitoring. Open-Insects makes it possible to evaluate algorithms for new species detection on several geographical open-set splits with varying difficulty. Furthermore, we present a test set recently collected in the wild with 59 species that are likely new to science. We evaluate a variety of open-set recognition algorithms, including post-hoc methods, training-time regularization, and training with auxiliary data, finding that the simple post-hoc approach of utilizing softmax scores remains a strong baseline. We also demonstrate how to leverage auxiliary data to improve the detection performance when the training dataset is limited. Our results provide timely insights to guide the development of computer vision methods for biodiversity monitoring and species discovery.


Microscopic Propagator Imaging (MPI) with Diffusion MRI

arXiv.org Artificial Intelligence

We propose Microscopic Propagator Imaging (MPI) as a novel method to retrieve the indices of the microscopic propagator which is the probability density function of water displacements due to diffusion within the nervous tissue microstructures. Unlike the Ensemble Average Propagator indices or the Diffusion Tensor Imaging metrics, MPI indices are independent from the mesoscopic organization of the tissue such as the presence of multiple axonal bundle directions and orientation dispersion. As a consequence, MPI indices are more specific to the volumes, sizes, and types of microstructures, like axons and cells, that are present in the tissue. Thus, changes in MPI indices can be more directly linked to alterations in the presence and integrity of microstructures themselves. The methodology behind MPI is rooted on zonal modeling of spherical harmonics, signal simulation, and machine learning regression, and is demonstrated on both synthetic and Human Diffusion MRI data.