Western Norway
Adaptive Nonlinear Data Assimilation through P-Spline Triangular Measure Transport
Lunde, Berent Å. S., Ramgraber, Maximilian
Non-Gaussian statistics are a challenge for data assimilation. Linear methods oversimplify the problem, yet fully nonlinear methods are often too expensive to use in practice. The best solution usually lies between these extremes. Triangular measure transport offers a flexible framework for nonlinear data assimilation. Its success, however, depends on how the map is parametrized. Too much flexibility leads to overfitting; too little misses important structure. To address this balance, we develop an adaptation algorithm that selects a parsimonious parametrization automatically. Our method uses P-spline basis functions and an information criterion as a continuous measure of model complexity. This formulation enables gradient descent and allows efficient, fine-scale adaptation in high-dimensional settings. The resulting algorithm requires no hyperparameter tuning. It adjusts the transport map to the appropriate level of complexity based on the system statistics and ensemble size. We demonstrate its performance in nonlinear, non-Gaussian problems, including a high-dimensional distributed groundwater model.
Designing value-aligned autonomous vehicles: from moral dilemmas to conflict-sensitive design
Imagine an autonomous car driving along a quiet suburban road when suddenly a dog runs onto the road. The system must brake hard and decide, within a fraction of a second, whether to swerve into oncoming traffic--where the other autonomous car might make space--to steer right and hit the roadside barrier, or to continue straight and injure the dog. The first two options risk only material damage; the last harms a living creature. Each choice is justifiable and involves trade-offs between safety, property and ethical concerns. However, today's autonomous systems are not designed to explicitly take such value-laden conflicts into account.
Is reading always better for your brain than listening to audiobooks?
Is reading always better for your brain than listening to audiobooks? Reading books and listening to audiobooks tap into different elements of cognition, each with their own benefits. So which one should you choose, and when? But when a friend recently asked me whether her daughter was getting the same cognitive benefits from an audiobook as she would from reading, my instinct was to think "she's enjoying a book, the format doesn't matter". However, when I dug into the science, I found the medium does shape the mind in subtly different but meaningful ways.
'I love you too!' My family's creepy, unsettling week with an AI toy
'Let's talk about something fun!' Grem the AI chatbot toy. 'Let's talk about something fun!' Grem the AI chatbot toy. 'I love you too!' My family's creepy, unsettling week with an AI toy The cuddly chatbot Grem is designed to'learn' your child's personality, while every conversation they have is recorded, then transcribed by a third party. It wasn't long before I wanted this experiment to be over ... 'I'm going to throw that thing into a river!" my wife says as she comes down the stairs looking frazzled after putting our four-year-old daughter to bed. To be clear, "that thing" is not our daughter, Emma*. It's Grem, an AI-powered stuffed alien toy that the musician Claire Boucher, better known as Grimes, helped develop with toy company Curio. Designed for kids aged three and over and built with OpenAI's technology, the toy is supposed to "learn" your child's personality and have fun, educational conversations with them. It's advertised as a healthier alternative to screen time and is ...
Privacy Preservation and Identity Tracing Prevention in AI-Driven Eye Tracking for Interactive Learning Environments
Rehman, Abdul, Dæhlen, Are, Heldal, Ilona, Lin, Jerry Chun-wei
Eye-tracking technology can aid in understanding neurodevelopmental disorders and tracing a person's identity. However, this technology poses a significant risk to privacy, as it captures sensitive information about individuals and increases the likelihood that data can be traced back to them. This paper proposes a human-centered framework designed to prevent identity backtracking while preserving the pedagogical benefits of AI-powered eye tracking in interactive learning environments. We explore how real-time data anonymization, ethical design principles, and regulatory compliance (such as GDPR) can be integrated to build trust and transparency. We first demonstrate the potential for backtracking student IDs and diagnoses in various scenarios using serious game-based eye-tracking data. We then provide a two-stage privacy-preserving framework that prevents participants from being tracked while still enabling diagnostic classification. The first phase covers four scenarios: I) Predicting disorder diagnoses based on different game levels. II) Predicting student IDs based on different game levels. III) Predicting student IDs based on randomized data. IV) Utilizing K-Means for out-of-sample data. In the second phase, we present a two-stage framework that preserves privacy. We also employ Federated Learning (FL) across multiple clients, incorporating a secure identity management system with dummy IDs and administrator-only access controls. In the first phase, the proposed framework achieved 99.3% accuracy for scenario 1, 63% accuracy for scenario 2, and 99.7% accuracy for scenario 3, successfully identifying and assigning a new student ID in scenario 4. In phase 2, we effectively prevented backtracking and established a secure identity management system with dummy IDs and administrator-only access controls, achieving an overall accuracy of 99.40%.
Calibrated and uncertain? Evaluating uncertainty estimates in binary classification models
Grefsrud, Aurora, Blaser, Nello, Buanes, Trygve
Rigorous statistical methods, including parameter estimation with accompanying uncertainties, underpin the validity of scientific discovery, especially in the natural sciences. With increasingly complex data models such as deep learning techniques, uncertainty quantification has become exceedingly difficult and a plethora of techniques have been proposed. In this case study, we use the unifying framework of approximate Bayesian inference combined with empirical tests on carefully created synthetic classification datasets to investigate qualitative properties of six different probabilistic machine learning algorithms for class probability and uncertainty estimation: (i) a neural network ensemble, (ii) neural network ensemble with conflictual loss, (iii) evidential deep learning, (iv) a single neural network with Monte Carlo Dropout, (v) Gaussian process classification and (vi) a Dirichlet process mixture model. We check if the algorithms produce uncertainty estimates which reflect commonly desired properties, such as being well calibrated and exhibiting an increase in uncertainty for out-of-distribution data points. Our results indicate that all algorithms are well calibrated, but none of the deep learning based algorithms provide uncertainties that consistently reflect lack of experimental evidence for out-of-distribution data points. We hope our study may serve as a clarifying example for researchers developing new methods of uncertainty estimation for scientific data-driven modeling.