Africa
A Human Rights-Based Approach to Responsible AI
Prabhakaran, Vinodkumar, Mitchell, Margaret, Gebru, Timnit, Gabriel, Iason
On the other hand, these research insights are meant to intervene on platforms that are globally present, serving a global population from diverse societies, cultures and values, with their own forms of injustices. A core concern in this arrangement is that of value imposition, where local values, i.e., values that are local to the regions where the interventions are built, implicitly shape and inform global systems without any or much room for discussion or contestation from those affected by those interventions. More specifically, interventions designed to address FATE failures necessarily impart a normative value system, but the values that guide the proposed solutions are rarely recognized as sites of contestation. This is problematic because while there may be ethical principles for ML that garner a degree of consensus across different value systems, in a pluralistic world this consensus is not something that should be assumed. Instead, we need to be explicit about the values that underpin the quest for ethical and just AI, and to cultivate an active debate about those values, critically examining and evaluating claims about them[28]. Another shortcoming of not being explicit about what normative value systems shape the interventions is the vagueness it entails, making it harder to arrive at a common vocabulary and shared understanding between computer scientists and civil society. Such a shared understanding is crucial to bridge the gap between research and practice, especially in a way that effectively supports the priorities of the latter constituency.
Evaluate & Evaluation on the Hub: Better Best Practices for Data and Model Measurements
von Werra, Leandro, Tunstall, Lewis, Thakur, Abhishek, Luccioni, Alexandra Sasha, Thrush, Tristan, Piktus, Aleksandra, Marty, Felix, Rajani, Nazneen, Mustar, Victor, Ngo, Helen, Sanseviero, Omar, ล aลกko, Mario, Villanova, Albert, Lhoest, Quentin, Chaumond, Julien, Mitchell, Margaret, Rush, Alexander M., Wolf, Thomas, Kiela, Douwe
Evaluation is a key part of machine learning (ML), yet there is a lack of support and tooling to enable its informed and systematic practice. We introduce Evaluate and Evaluation on the Hub--a set of tools to facilitate the evaluation of models and datasets in ML. Evaluate is a library to support best practices for measurements, metrics, and comparisons of data and models. Its goal is to support reproducibility of evaluation, centralize and document the evaluation process, and broaden Figure 1: Average number of evaluation datasets and evaluation to cover more facets of model metrics per paper, based on 10 random samples per performance. It includes over 50 efficient year from EMNLP proceedings over the past two canonical implementations for a variety of domains decades. More recent papers use more datasets and and scenarios, interactive documentation, metrics, while fewer of them report statistical significance and the ability to easily share implementations test results.
On the detrimental effect of invariances in the likelihood for variational inference
Kurle, Richard, Herbrich, Ralf, Januschowski, Tim, Wang, Yuyang, Gasthaus, Jan
Variational Bayesian posterior inference often requires simplifying approximations such as mean-field parametrisation to ensure tractability. However, prior work has associated the variational mean-field approximation for Bayesian neural networks with underfitting in the case of small datasets or large model sizes. In this work, we show that invariances in the likelihood function of over-parametrised models contribute to this phenomenon because these invariances complicate the structure of the posterior by introducing discrete and/or continuous modes which cannot be well approximated by Gaussian mean-field distributions. In particular, we show that the mean-field approximation has an additional gap in the evidence lower bound compared to a purpose-built posterior that takes into account the known invariances. Importantly, this invariance gap is not constant; it vanishes as the approximation reverts to the prior. We proceed by first considering translation invariances in a linear model with a single data point in detail. We show that, while the true posterior can be constructed from a mean-field parametrisation, this is achieved only if the objective function takes into account the invariance gap. Then, we transfer our analysis of the linear model to neural networks. Our analysis provides a framework for future work to explore solutions to the invariance problem.
A ResNet is All You Need? Modeling A Strong Baseline for Detecting Referable Diabetic Retinopathy in Fundus Images
Castilla, Tomรกs, Martรญnez, Marcela S., Leguรญa, Mercedes, Larrabide, Ignacio, Orlando, Josรฉ Ignacio
Deep learning is currently the state-of-the-art for automated detection of referable diabetic retinopathy (DR) from color fundus photographs (CFP). While the general interest is put on improving results through methodological innovations, it is not clear how good these approaches perform compared to standard deep classification models trained with the appropriate settings. In this paper we propose to model a strong baseline for this task based on a simple and standard ResNet-18 architecture. To this end, we built on top of prior art by training the model with a standard preprocessing strategy but using images from several public sources and an empirically calibrated data augmentation setting. To evaluate its performance, we covered multiple clinically relevant perspectives, including image and patient level DR screening, discriminating responses by input quality and DR grade, assessing model uncertainties and analyzing its results in a qualitative manner. With no other methodological innovation than a carefully designed training, our ResNet model achieved an AUC = 0.955 (0.953 - 0.956) on a combined test set of 61007 test images from different public datasets, which is in line or even better than what other more complex deep learning models reported in the literature. Similar AUC values were obtained in 480 images from two separate in-house databases specially prepared for this study, which emphasize its generalization ability. This confirms that standard networks can still be strong baselines for this task if properly trained.
Temporal Spatial Decomposition and Fusion Network for Time Series Forecasting
Feature engineering is required to obtain better results for time series forecasting, and decomposition is a crucial one. One decomposition approach often cannot be used for numerous forecasting tasks since the standard time series decomposition lacks flexibility and robustness. Traditional feature selection relies heavily on preexisting domain knowledge, has no generic methodology, and requires a lot of labor. However, most time series prediction models based on deep learning typically suffer from interpretability issue, so the "black box" results lead to a lack of confidence. To deal with the above issues forms the motivation of the thesis. In the paper we propose TSDFNet as a neural network with self-decomposition mechanism and an attentive feature fusion mechanism, It abandons feature engineering as a preprocessing convention and creatively integrates it as an internal module with the deep model. The self-decomposition mechanism empowers TSDFNet with extensible and adaptive decomposition capabilities for any time series, users can choose their own basis functions to decompose the sequence into temporal and generalized spatial dimensions. Attentive feature fusion mechanism has the ability to capture the importance of external variables and the causality with target variables. It can automatically suppress the unimportant features while enhancing the effective ones, so that users do not have to struggle with feature selection. Moreover, TSDFNet is easy to look into the "black box" of the deep neural network by feature visualization and analyze the prediction results. We demonstrate performance improvements over existing widely accepted models on more than a dozen datasets, and three experiments showcase the interpretability of TSDFNet.
GNSS/MEMS-INS Integration for Drone Navigation using EKF on Lie Groups
Fernandes, Marcos R., Magalhรฃes, Giorgio M., Cรกceres, Yusef, Val, Joรฃo B. R. do
Building upon the theory of Kalman Filtering on Lie Groups, this paper describes an Extended Kalman Filter and Smoother for Loosely Coupled Integration of GNSS/INS tailored for post-processing applications. The approach employs a dynamic model on a matrix Lie Group that aggregates position, velocity, attitude, and the IMU biases as a single element of a Lie group. The development was motivated by a drone-borne Differential Interferometric SAR (DinSAR) application, which requires high-precision navigation information for short-flight missions using low-cost MEMS sensors. The filter and the Rauch-Tung-Striebel (RTS) smoother are both implemented and validated. The paper also presents a novel algorithm to initialize the heading value as an alternative to gyro-compassing or magnetometer-based alignments. The Mahalanobis Distance and the $\chi^2$-test are employed during the filter update step to address the practical issue of outlier rejection for the GNSS measurements. The paper uses synthetic data to compare classic navigation schemes based on multiplicative quaternions and Euler angles. Finally, real data experiments demonstrate that the Kalman Filter based on Lie Groups performs better DinSAR processing than state-of-the-art commercial software.
The Power of Transfer Learning in Agricultural Applications: AgriNet
Sahili, Zahraa Al, Awad, Mariette
Advances in deep learning and transfer learning have paved the way for various automation classification tasks in agriculture, including plant diseases, pests, weeds, and plant species detection. However, agriculture automation still faces various challenges, such as the limited size of datasets and the absence of plant-domain-specific pretrained models. Domain specific pretrained models have shown state of art performance in various computer vision tasks including face recognition and medical imaging diagnosis. In this paper, we propose AgriNet dataset, a collection of 160k agricultural images from more than 19 geographical locations, several images captioning devices, and more than 423 classes of plant species and diseases. We also introduce AgriNet models, a set of pretrained models on five ImageNet architectures: VGG16, VGG19, Inception-v3, InceptionResNet-v2, and Xception. AgriNet-VGG19 achieved the highest classification accuracy of 94 % and the highest F1-score of 92%. Additionally, all proposed models were found to accurately classify the 423 classes of plant species, diseases, pests, and weeds with a minimum accuracy of 87% for the Inception-v3 model.Finally, experiments to evaluate of superiority of AgriNet models compared to ImageNet models were conducted on two external datasets: pest and plant diseases dataset from Bangladesh and a plant diseases dataset from Kashmir.
FLoBC: A Decentralized Blockchain-Based Federated Learning Framework
Ghanem, Mohamed, Dawoud, Fadi, Gamal, Habiba, Soliman, Eslam, Sharara, Hossam, El-Batt, Tamer
The rapid expansion of data worldwide invites the need for more distributed solutions in order to apply machine learning on a much wider scale. The resultant distributed learning systems can have various degrees of centralization. In this work, we demonstrate our solution FLoBC for building a generic decentralized federated learning system using blockchain technology, accommodating any machine learning model that is compatible with gradient descent optimization. We present our system design comprising the two decentralized actors: trainer and validator, alongside our methodology for ensuring reliable and efficient operation of said system. Finally, we utilize FLoBC as an experimental sandbox to compare and contrast the effects of trainer-to-validator ratio, reward-penalty policy, and model synchronization schemes on the overall system performance, ultimately showing by example that a decentralized federated learning system is indeed a feasible alternative to more centralized architectures.
Tesla to REMOVE sensors from new cars in a bet on cameras and AI - amid scrutiny of crashes
Tesla is removing sensors from its cars as it shifts toward a system based solely on eight cameras that feed information into its self-driving artificial intelligence. Ultrasonic sensors (USS), which emit high-frequency sounds that bounce off of potential obstacles, will in the coming months be phased out of new Model 3 and Model Y vehicles sold in North America, Europe, the Middle East and Taiwan, and then globally. They will be phased out of Model 4 and Model X cars next year. The announcement from the company led by CEO Elon Musk comes as Tesla is facing intense regulatory and legal scrutiny over a series of crashes involving its self-driving system. Data from the National Highway Traffic Safety Administration (NHTSA) identified 392 reported accidents as of May 2022 involving cars with assisted-driver features - out of those, 273 involved Teslas. Tesla is removing sensors from its cars as it shifts toward a system based solely on eight cameras that feed information into its self-driving artificial intelligence.
Zipline drones will deliver medicine to communities in Utah
Zipline has teamed up with a healthcare provider servicing the Intermountain Region in the US to deliver medicine to customers using its drones. The company has started doing drone deliveries to select Intermountain Healthcare patients in the Salt Lake Valley area. For now, it can only do drops for local communities within several miles of its distribution center. Zipline intends to add more centers over the next five years, though, so it can eventually expand beyond Salt Lake Valley and deliver medicine throughout Utah. As TechCrunch notes, Zipline has long been deploying drones for delivery in Africa, and it wasn't until the pandemic that it started doing drops in the US.