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Granularity at Scale: Estimating Neighborhood Socioeconomic Indicators from High-Resolution Orthographic Imagery and Hybrid Learning

arXiv.org Artificial Intelligence

Many areas of the world are without basic information on the socioeconomic well-being of the residing population due to limitations in existing data collection methods. Overhead images obtained remotely, such as from satellite or aircraft, can help serve as windows into the state of life on the ground and help "fill in the gaps" where community information is sparse, with estimates at smaller geographic scales requiring higher resolution sensors. Concurrent with improved sensor resolutions, recent advancements in machine learning and computer vision have made it possible to quickly extract features from and detect patterns in image data, in the process correlating these features with other information. In this work, we explore how well two approaches, a supervised convolutional neural network and semi-supervised clustering based on bag-of-visual-words, estimate population density, median household income, and educational attainment of individual neighborhoods from publicly available high-resolution imagery of cities throughout the United States. Results and analyses indicate that features extracted from the imagery can accurately estimate the density (R$^2$ up to 0.81) of neighborhoods, with the supervised approach able to explain about half the variation in a population's income and education. In addition to the presented approaches serving as a basis for further geographic generalization, the novel semi-supervised approach provides a foundation for future work seeking to estimate fine-scale information from aerial imagery without the need for label data.


Can LLM-Generated Misinformation Be Detected?

arXiv.org Artificial Intelligence

The advent of Large Language Models (LLMs) has made a transformative impact. However, the potential that LLMs such as ChatGPT can be exploited to generate misinformation has posed a serious concern to online safety and public trust. A fundamental research question is: will LLM-generated misinformation cause more harm than human-written misinformation? We propose to tackle this question from the perspective of detection difficulty. We first build a taxonomy of LLM-generated misinformation. Then we categorize and validate the potential real-world methods for generating misinformation with LLMs. Then, through extensive empirical investigation, we discover that LLM-generated misinformation can be harder to detect for humans and detectors compared to human-written misinformation with the same semantics, which suggests it can have more deceptive styles and potentially cause more harm. We also discuss the implications of our discovery on combating misinformation in the age of LLMs and the countermeasures.


Detection of Unknown-Unknowns in Human-in-Plant Human-in-Loop Systems Using Physics Guided Process Models

arXiv.org Artificial Intelligence

Unknown-unknowns are operational scenarios in systems that are not accounted for in the design and test phase. In such scenarios, the operational behavior of the Human-in-loop (HIL) Human-in-Plant (HIP) systems is not guaranteed to meet requirements such as safety and efficacy. We propose a novel framework for analyzing the operational output characteristics of safety-critical HIL-HIP systems that can discover unknown-unknown scenarios and evaluate potential safety hazards. We propose dynamics-induced hybrid recurrent neural networks (DiH-RNN) to mine a physics-guided surrogate model (PGSM) that checks for deviation of the cyber-physical system (CPS) from safety-certified operational characteristics. The PGSM enables early detection of unknown-unknowns based on the physical laws governing the system. We demonstrate the detection of operational changes in an Artificial Pancreas(AP) due to unknown insulin cartridge errors.


VisoGender: A dataset for benchmarking gender bias in image-text pronoun resolution

arXiv.org Artificial Intelligence

We introduce VisoGender, a novel dataset for benchmarking gender bias in vision-language models. We focus on occupation-related biases within a hegemonic system of binary gender, inspired by Winograd and Winogender schemas, where each image is associated with a caption containing a pronoun relationship of subjects and objects in the scene. VisoGender is balanced by gender representation in professional roles, supporting bias evaluation in two ways: i) resolution bias, where we evaluate the difference between pronoun resolution accuracies for image subjects with gender presentations perceived as masculine versus feminine by human annotators and ii) retrieval bias, where we compare ratios of professionals perceived to have masculine and feminine gender presentations retrieved for a gender-neutral search query. We benchmark several state-of-the-art vision-language models and find that they demonstrate bias in resolving binary gender in complex scenes. While the direction and magnitude of gender bias depends on the task and the model being evaluated, captioning models are generally less biased than Vision-Language Encoders. Dataset and code are available at https://github.com/oxai/visogender


A Dynamic Programming Framework for Optimal Planning of Redundant Robots Along Prescribed Paths With Kineto-Dynamic Constraints

arXiv.org Artificial Intelligence

Abstract--Offline optimal planning of trajectories for redundant we go through the whole process of planning and executing robots along prescribed task space paths is usually a time-optimal trajectory on a real robot, and discuss some broken down into two consecutive processes: first, the task practical details, such as trajectory smoothness and actuator space path is inverted to obtain a joint space path, then, the saturation, aiding the practitioners in deploying our algorithm latter is parametrized with a time law. If the two processes effectively. Currently, the algorithm's applicability is limited are separated, they cannot optimize the same objective function, to those cases where hours are available for planning, hence ultimately providing sub-optimal results. In this paper, it is not well-suited for those cases where the robot activity a unified approach is presented where dynamic programming has to change frequently. By replacing the underlying dynamic is the underlying optimization technique. Its flexibility allows programming engine with a different methodology, such as accommodating arbitrary constraints and objective functions, randomized algorithms, the planning time could be controlled thus providing a generic framework for optimal planning of real to be upper-bounded, thus returning the most efficient solution systems. To demonstrate its applicability to a real world scenario, that can be achieved in the time available for reconfiguring the the framework is instantiated for time-optimality on Franka production. Other applications of interest include optimal ground Emika's Panda robot.


GP+: A Python Library for Kernel-based learning via Gaussian Processes

arXiv.org Machine Learning

In this paper we introduce GP+, an open-source library for kernel-based learning via Gaussian processes (GPs) which are powerful statistical models that are completely characterized by their parametric covariance and mean functions. GP+ is built on PyTorch and provides a user-friendly and object-oriented tool for probabilistic learning and inference. As we demonstrate with a host of examples, GP+ has a few unique advantages over other GP modeling libraries. We achieve these advantages primarily by integrating nonlinear manifold learning techniques with GPs' covariance and mean functions. As part of introducing GP+, in this paper we also make methodological contributions that (1) enable probabilistic data fusion and inverse parameter estimation, and (2) equip GPs with parsimonious parametric mean functions which span mixed feature spaces that have both categorical and quantitative variables. We demonstrate the impact of these contributions in the context of Bayesian optimization, multi-fidelity modeling, sensitivity analysis, and calibration of computer models.


On Classification-Calibration of Gamma-Phi Losses

arXiv.org Machine Learning

Gamma-Phi losses constitute a family of multiclass classification loss functions that generalize the logistic and other common losses, and have found application in the boosting literature. We establish the first general sufficient condition for the classification-calibration (CC) of such losses. To our knowledge, this sufficient condition gives the first family of nonconvex multiclass surrogate losses for which CC has been fully justified. In addition, we show that a previously proposed sufficient condition is in fact not sufficient. This contribution highlights a technical issue that is important in the study of multiclass CC but has been neglected in prior work.


Randomly pivoted Cholesky: Practical approximation of a kernel matrix with few entry evaluations

arXiv.org Machine Learning

The randomly pivoted partial Cholesky algorithm (RPCholesky) computes a factorized rank-k approximation of an N x N positive-semidefinite (psd) matrix. RPCholesky requires only (k + 1) N entry evaluations and O(k^2 N) additional arithmetic operations, and it can be implemented with just a few lines of code. The method is particularly useful for approximating a kernel matrix. This paper offers a thorough new investigation of the empirical and theoretical behavior of this fundamental algorithm. For matrix approximation problems that arise in scientific machine learning, experiments show that RPCholesky matches or beats the performance of alternative algorithms. Moreover, RPCholesky provably returns low-rank approximations that are nearly optimal. The simplicity, effectiveness, and robustness of RPCholesky strongly support its use in scientific computing and machine learning applications.


Tesla's response to the DMV's false-advertising allegations: What took so long?

Los Angeles Times

Seven years after Tesla released the automated driving feature it calls Full Self-Driving, and two-and-a-half years after opening an investigation into it, the California Department of Motor Vehicles is alleging false advertising, which could carry serious implications for the electric car maker. Tesla is defending itself by saying, in effect, that the DMV let the company slide for so many years, the case no longer has legal standing. Plus, the company, run by Chief Executive Elon Musk, says the DMV is violating its free speech rights under the U.S. Constitution's 1st Amendment. The DMV "has been aware that Tesla has been using the brand names Autopilot and Full Self-Driving Capability since Tesla started using those names in 2014 and 2016 respectively," the company said in a response filed in a state administrative court Friday. The company "relied upon [the DMV's] implicit approval of these brand names" and "the DMV chose not to take any action against Tesla or otherwise communicate to Tesla that its advertising or use of these brand names was or might be problematic," the response notice states.


Can the EU's plan to regulate AI keep up with rapidly evolving tech?

New Scientist

The European Union has announced that the text of its long-awaited AI Act has been agreed, following a marathon 36-hour debate between the European Commission, European Council and European Parliament. The law is intended to regulate artificial intelligence in a similar way to finance and healthcare, by protecting EU citizens and ensuring that countries, companies and military contractors act responsibly.