Africa
Tension Estimation and Localization for a Tethered Micro Aerial Robot
Martins, Ricardo, Basiri, Meysam
This work focuses on the study of tethered fights of a micro quadcopter, with the aim of supplying continuous power to a small-sized aerial robot. Multiple features for facilitating the interaction between a tethered micro quadcopter and a ground base are described in this paper. Firstly, a tether model based on the catenary curve is presented that describes a quadcopter tethered to a point in space. Furthermore, a method capable of estimating the tension applied to the quadcopter, based only on the inertial information from the IMU sensors and the motor thrusts, is presented. Finally, a novel method for localizing the quadcopter by exploiting the tension imposed by the tether and the shape of the tether is described. The proposed methods are evaluated both in simulation and in real world prototype.
Less is More: Understanding Word-level Textual Adversarial Attack via n-gram Frequency Descend
Lu, Ning, Liu, Shengcai, Zhang, Zhirui, Wang, Qi, Liu, Haifeng, Tang, Ke
Word-level textual adversarial attacks have achieved striking performance in fooling natural language processing models. However, the fundamental questions of why these attacks are effective, and the intrinsic properties of the adversarial examples (AEs), are still not well understood. This work attempts to interpret textual attacks through the lens of $n$-gram frequency. Specifically, it is revealed that existing word-level attacks exhibit a strong tendency toward generation of examples with $n$-gram frequency descend ($n$-FD). Intuitively, this finding suggests a natural way to improve model robustness by training the model on the $n$-FD examples. To verify this idea, we devise a model-agnostic and gradient-free AE generation approach that relies solely on the $n$-gram frequency information, and further integrate it into the recently proposed convex hull framework for adversarial training. Surprisingly, the resultant method performs quite similarly to the original gradient-based method in terms of model robustness. These findings provide a human-understandable perspective for interpreting word-level textual adversarial attacks, and a new direction to improve model robustness.
What do Language Models know about word senses? Zero-Shot WSD with Language Models and Domain Inventories
Sainz, Oscar, de Lacalle, Oier Lopez, Agirre, Eneko, Rigau, German
Language Models are the core for almost any Natural Language Processing system nowadays. One of their particularities is their contextualized representations, a game changer feature when a disambiguation between word senses is necessary. In this paper we aim to explore to what extent language models are capable of discerning among senses at inference time. We performed this analysis by prompting commonly used Languages Models such as BERT or RoBERTa to perform the task of Word Sense Disambiguation (WSD). We leverage the relation between word senses and domains, and cast WSD as a textual entailment Figure 1: An example of the Word Sense Disambiguation problem, where the different hypothesis refer task converted to Textual Entailment, where the hypothesis to the domains of the word senses. Our results refer to the possible domains of word senses.
Natural Language Processing for Policymaking
Language is an important form of data in politics. Constituents express their stances and needs in text such as social media and survey responses. Politicians conduct campaigns through debates, statements of policy positions, and social media. Government staff needs to compile information from various documents to assist in decision-making. Textual data is also prevalent through the documents and debates in the legislation process, negotiations and treaties to resolve international conflicts, and media such as news reports, social media, party platforms, and manifestos. Natural language processing (NLP) is the study of computational methods to automatically analyze text and extract meaningful information for subsequent analysis. The importance of NLP for policymaking has been highlighted since the last century (Gigley, 1993).
Climate Intervention Analysis using AI Model Guided by Statistical Physics Principles
Kim, Soo Kyung, Ramea, Kalai, Cachay, Salva Rühling, Hirasawa, Haruki, Hazarika, Subhashis, Hingmire, Dipti, Mitra, Peetak, Rasch, Philip J., Singh, Hansi A.
The availability of training data remains a significant obstacle for the implementation of machine learning in scientific applications. In particular, estimating how a system might respond to external forcings or perturbations requires specialized labeled data or targeted simulations, which may be computationally intensive to generate at scale. In this study, we propose a novel solution to this challenge by utilizing a principle from statistical physics known as the Fluctuation-Dissipation Theorem (FDT) to discover knowledge using an AI model that can rapidly produce scenarios for different external forcings. By leveraging FDT, we are able to extract information encoded in a large dataset produced by Earth System Models, which includes 8250 years of internal climate fluctuations, to estimate the climate system's response to forcings. Our model, AiBEDO, is capable of capturing the complex, multi-timescale effects of radiation perturbations on global and regional surface climate, allowing for a substantial acceleration of the exploration of the impacts of spatially-heterogenous climate forcers. To demonstrate the utility of AiBEDO, we use the example of a climate intervention technique called Marine Cloud Brightening, with the ultimate goal of optimizing the spatial pattern of cloud brightening to achieve regional climate targets and prevent known climate tipping points. While we showcase the effectiveness of our approach in the context of climate science, it is generally applicable to other scientific disciplines that are limited by the extensive computational demands of domain simulation models. Source code of AiBEDO framework is made available at https://github.com/kramea/kdd_aibedo. A sample dataset is made available at https://doi.org/10.5281/zenodo.7597027. Additional data available upon request.
AutoWS: Automated Weak Supervision Framework for Text Classification
Bohra, Abhinav, Nguyen, Huy, Khatwani, Devashish
Creating large, good quality labeled data has become one of the major bottlenecks for developing machine learning applications. Multiple techniques have been developed to either decrease the dependence of labeled data (zero/few-shot learning, weak supervision) or to improve the efficiency of labeling process (active learning). Among those, Weak Supervision has been shown to reduce labeling costs by employing hand crafted labeling functions designed by domain experts. We propose AutoWS -- a novel framework for increasing the efficiency of weak supervision process while decreasing the dependency on domain experts. Our method requires a small set of labeled examples per label class and automatically creates a set of labeling functions to assign noisy labels to numerous unlabeled data. Noisy labels can then be aggregated into probabilistic labels used by a downstream discriminative classifier. Our framework is fully automatic and requires no hyper-parameter specification by users. We compare our approach with different state-of-the-art work on weak supervision and noisy training. Experimental results show that our method outperforms competitive baselines.
Deep Class-Incremental Learning: A Survey
Zhou, Da-Wei, Wang, Qi-Wei, Qi, Zhi-Hong, Ye, Han-Jia, Zhan, De-Chuan, Liu, Ziwei
Deep models, e.g., CNNs and Vision Transformers, have achieved impressive achievements in many vision tasks in the closed world. However, novel classes emerge from time to time in our ever-changing world, requiring a learning system to acquire new knowledge continually. For example, a robot needs to understand new instructions, and an opinion monitoring system should analyze emerging topics every day. Class-Incremental Learning (CIL) enables the learner to incorporate the knowledge of new classes incrementally and build a universal classifier among all seen classes. Correspondingly, when directly training the model with new class instances, a fatal problem occurs -- the model tends to catastrophically forget the characteristics of former ones, and its performance drastically degrades. There have been numerous efforts to tackle catastrophic forgetting in the machine learning community. In this paper, we survey comprehensively recent advances in deep class-incremental learning and summarize these methods from three aspects, i.e., data-centric, model-centric, and algorithm-centric. We also provide a rigorous and unified evaluation of 16 methods in benchmark image classification tasks to find out the characteristics of different algorithms empirically. Furthermore, we notice that the current comparison protocol ignores the influence of memory budget in model storage, which may result in unfair comparison and biased results. Hence, we advocate fair comparison by aligning the memory budget in evaluation, as well as several memory-agnostic performance measures. The source code to reproduce these evaluations is available at https://github.com/zhoudw-zdw/CIL_Survey/
World University Law School - World University and School Wiki
Welcome to World University and School Wiki which anyone can add to or edit. WUaS would like to offer online CLE credits with these great universities, anticipating accrediting WUaS Law Schools in 204 countries. California, the state in which WUaS is incorporated, has 12 online law schools (none of these are ABA approved, but anyone can sit the California Bar exam, regardless of such approval, as I understand it), at present, and WUaS would like to develop another online MIT OCW/Harvard-centric law school, and eventually accredit in all 204 countries in the world, in main languages in those countries, beginning with the 6 United Nations' languages. Online Law Schools Have Yet to Pass the Bar: Many argue that fully online programs aren't the path to a traditional legal career]. WUaS is planning for a "Admitted Students' Day" for the first, matriculating Bachelor's degree class, on or around Saturday, April 14th, 2014, and the second Saturday of April for other degrees in the future.
Predicting Metadata for Humanitarian Datasets Using GPT-3
Responding to humanitarian disasters quickly, better still, anticipating them can save lives [1]. Data is key to this, not just having lots of data, but clean data which is well understood [2] in order to create a clear view of the situation on the ground. In many cases this critical data is stored in hundreds of small spreadsheets, so piecing them altogether can be time consuming and difficult to maintain as new data comes in during a humanitarian incident. Automating the process of data discovery would potentially speed responses and improve outcomes for affected people. One way to make discovery easier is to ensure that tabular data has metadata describing each column.
Collective Robustness Certificates: Exploiting Interdependence in Graph Neural Networks
Schuchardt, Jan, Bojchevski, Aleksandar, Gasteiger, Johannes, Günnemann, Stephan
In tasks like node classification, image segmentation, and named-entity recognition we have a classifier that simultaneously outputs multiple predictions (a vector of labels) based on a single input, i.e. a single graph, image, or document respectively. Existing adversarial robustness certificates consider each prediction independently and are thus overly pessimistic for such tasks. They implicitly assume that an adversary can use different perturbed inputs to attack different predictions, ignoring the fact that we have a single shared input. We propose the first collective robustness certificate which computes the number of predictions that are simultaneously guaranteed to remain stable under perturbation, i.e. cannot be attacked. We focus on Graph Neural Networks and leverage their locality property - perturbations only affect the predictions in a close neighborhood - to fuse multiple single-node certificates into a drastically stronger collective certificate. For example, on the Citeseer dataset our collective certificate for node classification increases the average number of certifiable feature perturbations from 7 to 351 . Most classifiers are vulnerable to adversarial attacks (Akhtar & Mian, 2018; Hao-Chen et al., 2020). Slight perturbations of the data are often sufficient to manipulate their predictions. Even in scenarios where attackers are not present it is critical to ensure that models are robust since data can be noisy, incomplete, or anomalous. We study classifiers that collectively output many predictions based on a single input. This includes node classification, link prediction, molecular property prediction, image segmentation, part-of-speech tagging, named-entity recognition, and many other tasks. V arious techniques have been proposed to improve the adversarial robustness of such models. One example is adversarial training (Goodfellow et al., 2015), which has been applied to part-of-speech tagging (Han et al., 2020), semantic segmentation (Xu et al., 2020b) and node classification (Feng et al., 2019). Graph-related tasks in particular have spawned a rich assortment of techniques. These include Bayesian models (Feng et al., 2020), data-augmentation methods (Entezari et al., 2020) and various robust network architectures (Zhu et al., 2019; Geisler et al., 2020). There are also robust loss functions which either explicitly model an adversary trying to cause misclassifications (Zhou & V orobeychik, 2020) or use regularization terms derived from robustness certificates (Z ugner & G unnemann, 2019). Other methods try to detect adversarially perturbed graphs (Zhang et al., 2019; Xu et al., 2020a) or directly correct perturbations using generative models (Zhang & Ma, 2020).