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Y Social: an LLM-powered Social Media Digital Twin

arXiv.org Artificial Intelligence

Online social media (OSM henceforth) have revolutionized the way we exchange information. From the user's perspective, these digital ecosystems are largely effortless [136], enabling convenient ways of exchanging personal content [1], seeking information [129] and synchronizing with others [37]. This convenience has catalyzed a massive digital shift in social and information exchanges from offline to online settings [136], which has provided novel access to massive amounts of online data regarding human behaviour [141]. Unconstrained by geographical barriers, the massive adoption of social media has given rise to novel phenomena that are absent in in-person interactions, such as the influence of complexity and artificial intelligence. Complexity in social media is strongly related to the motto "more is different" [7]: the idea that the co-occurrence of many, even similar, interactions within the same context can lead to unexpected phenomena. Examples include acts as simple and seemingly insignificant as following another user, or re-sharing content. Taken individually, these actions can be understood in terms of a user's activity, psychology, and engagement [91, 97, 141], but when repeated by vast amounts of users, these actions can determine the unexpected rise


Risks, Causes, and Mitigations of Widespread Deployments of Large Language Models (LLMs): A Survey

arXiv.org Artificial Intelligence

Recent advancements in Large Language Models (LLMs), such as ChatGPT and LLaMA, have significantly transformed Natural Language Processing (NLP) with their outstanding abilities in text generation, summarization, and classification. Nevertheless, their widespread adoption introduces numerous challenges, including issues related to academic integrity, copyright, environmental impacts, and ethical considerations such as data bias, fairness, and privacy. The rapid evolution of LLMs also raises concerns regarding the reliability and generalizability of their evaluations. This paper offers a comprehensive survey of the literature on these subjects, systematically gathered and synthesized from Google Scholar. Our study provides an in-depth analysis of the risks associated with specific LLMs, identifying sub-risks, their causes, and potential solutions. Furthermore, we explore the broader challenges related to LLMs, detailing their causes and proposing mitigation strategies. Through this literature analysis, our survey aims to deepen the understanding of the implications and complexities surrounding these powerful models.


Collecting Larg-Scale Robotic Datasets on a High-Speed Mobile Platform

arXiv.org Artificial Intelligence

Mobile robotics datasets are essential for research on robotics, for example for research on Simultaneous Localization and Mapping (SLAM). Therefore the ShanghaiTech Mapping Robot was constructed, that features a multitude high-performance sensors and a 16-node cluster to collect all this data. That robot is based on a Clearpath Husky mobile base with a maximum speed of 1 meter per second. This is fine for indoor datasets, but to collect large-scale outdoor datasets a faster platform is needed. This system paper introduces our high-speed mobile platform for data collection. The mapping robot is secured on the rear-steered flatbed car with maximum field of view. Additionally two encoders collect odometry data from two of the car wheels and an external sensor plate houses a downlooking RGB and event camera. With this setup a dataset of more than 10km in the underground parking garage and the outside of our campus was collected and is published with this paper.


Ontological Relations from Word Embeddings

arXiv.org Artificial Intelligence

It has been reliably shown that the similarity of word embeddings obtained from popular neural models such as BERT approximates effectively a form of semantic similarity of the meaning of those words. It is therefore natural to wonder if those embeddings contain enough information to be able to connect those meanings through ontological relationships such as the one of subsumption. If so, large knowledge models could be built that are capable of semantically relating terms based on the information encapsulated in word embeddings produced by pre-trained models, with implications not only for ontologies (ontology matching, ontology evolution, etc.) but also on the ability to integrate ontological knowledge in neural models. In this paper, we test how embeddings produced by several pre-trained models can be used to predict relations existing between classes and properties of popular upper-level and general ontologies. We show that even a simple feed-forward architecture on top of those embeddings can achieve promising accuracies, with varying generalisation abilities depending on the input data. To achieve that, we produce a dataset that can be used to further enhance those models, opening new possibilities for applications integrating knowledge from web ontologies.


A Systematic Review on Long-Tailed Learning

arXiv.org Artificial Intelligence

Long-tailed data is a special type of multi-class imbalanced data with a very large amount of minority/tail classes that have a very significant combined influence. Long-tailed learning aims to build high-performance models on datasets with long-tailed distributions, which can identify all the classes with high accuracy, in particular the minority/tail classes. It is a cutting-edge research direction that has attracted a remarkable amount of research effort in the past few years. In this paper, we present a comprehensive survey of latest advances in long-tailed visual learning. We first propose a new taxonomy for long-tailed learning, which consists of eight different dimensions, including data balancing, neural architecture, feature enrichment, logits adjustment, loss function, bells and whistles, network optimization, and post hoc processing techniques. Based on our proposed taxonomy, we present a systematic review of long-tailed learning methods, discussing their commonalities and alignable differences. We also analyze the differences between imbalance learning and long-tailed learning approaches. Finally, we discuss prospects and future directions in this field.


Coverage Path Planning For Minimizing Expected Time to Search For an Object With Continuous Sensing

arXiv.org Artificial Intelligence

In this paper, we present several results of both theoretical as well as practical interests. First, we propose the quota lawn mowing problem, an extension of the classic lawn mowing problem in computational geometry, as follows: given a quota of coverage, compute the shortest lawn mowing route to achieve said quota. We give constant-factor approximations for the quota lawn mowing problem. Second, we investigate the expected detection time minimization problem in geometric coverage path planning with local, continuous sensory information. We provide the first approximation algorithm with provable error bounds with pseudopolynomial running time. Our ideas also extend to another search mechanism, namely visibility-based search, which is related to the watchman route problem. We complement our theoretical analysis with some simple but effective heuristics for finding an object in minimum expected time, on which we provide simulation results.


Illustrating Classic Brazilian Books using a Text-To-Image Diffusion Model

arXiv.org Artificial Intelligence

In recent years, Generative Artificial Intelligence (GenAI) has undergone a profound transformation in addressing intricate tasks involving diverse modalities such as textual, auditory, visual, and pictorial generation. Within this spectrum, text-to-image (TTI) models have emerged as a formidable approach to generating varied and aesthetically appealing compositions, spanning applications from artistic creation to realistic facial synthesis, and demonstrating significant advancements in computer vision, image processing, and multimodal tasks. The advent of Latent Diffusion Models (LDMs) signifies a paradigm shift in the domain of AI capabilities. This article delves into the feasibility of employing the Stable Diffusion LDM to illustrate literary works. For this exploration, seven classic Brazilian books have been selected as case studies. The objective is to ascertain the practicality of this endeavor and to evaluate the potential of Stable Diffusion in producing illustrations that augment and enrich the reader's experience. We will outline the beneficial aspects, such as the capacity to generate distinctive and contextually pertinent images, as well as the drawbacks, including any shortcomings in faithfully capturing the essence of intricate literary depictions. Through this study, we aim to provide a comprehensive assessment of the viability and efficacy of utilizing AI-generated illustrations in literary contexts, elucidating both the prospects and challenges encountered in this pioneering application of technology.


What comes after transformers? -- A selective survey connecting ideas in deep learning

arXiv.org Artificial Intelligence

Transformers have become the de-facto standard model in artificial intelligence since 2017 despite numerous shortcomings ranging from energy inefficiency to hallucinations. Research has made a lot of progress in improving elements of transformers, and, more generally, deep learning manifesting in many proposals for architectures, layers, optimization objectives, and optimization techniques. For researchers it is difficult to keep track of such developments on a broader level. We provide a comprehensive overview of the many important, recent works in these areas to those who already have a basic understanding of deep learning. Our focus differs from other works, as we target specifically novel, alternative potentially disruptive approaches to transformers as well as successful ideas of recent deep learning. We hope that such a holistic and unified treatment of influential, recent works and novel ideas helps researchers to form new connections between diverse areas of deep learning. We identify and discuss multiple patterns that summarize the key strategies for successful innovations over the last decade as well as works that can be seen as rising stars. Especially, we discuss attempts on how to improve on transformers covering (partially) proven methods such as state space models but also including far-out ideas in deep learning that seem promising despite not achieving state-of-the-art results. We also cover a discussion on recent state-of-the-art models such as OpenAI's GPT series and Meta's LLama models and, Google's Gemini model family.


Review of Explainable Graph-Based Recommender Systems

arXiv.org Artificial Intelligence

Explainability of recommender systems has become essential to ensure users' trust and satisfaction. Various types of explainable recommender systems have been proposed including explainable graph-based recommender systems. This review paper discusses state-of-the-art approaches of these systems and categorizes them based on three aspects: learning methods, explaining methods, and explanation types. It also explores the commonly used datasets, explainability evaluation methods, and future directions of this research area. Compared with the existing review papers, this paper focuses on explainability based on graphs and covers the topics required for developing novel explainable graph-based recommender systems.


A Culturally-Aware Tool for Crowdworkers: Leveraging Chronemics to Support Diverse Work Styles

arXiv.org Artificial Intelligence

This issue usually stems from the assumption that crowdworkers are a homogeneous group [56], neglecting their diverse cultural backgrounds [90]. Moreover, a notable trend in design has emerged advocating for minimizing cultural impact in work interfaces, aiming for global uniformity in their design rather than customizing these systems to accommodate cultural nuances [133, 134, 193]. Consequently, many work interfaces have strived for uniform standards, and have ignored worker diversity [76, 84, 88]. However, interfaces often reflect the cultural biases of their designers [18], inadvertently embedding their cultural norms [146, 150, 177]. This can lead to designs that unintentionally require "outside workers" to adapt or modify their behaviors [126, 177], potentially hindering their success and effectiveness in their jobs [24, 60, 64, 85]. A solution can be to create culturally aware tools for crowdworkers, yet research into integrating culture theory into such designs remains limited [108, 118, 163]. Further research is crucial to assess these systems' effectiveness and their potential benefits for crowdworkers from varied cultural backgrounds. To address this knowledge gap, we focus on designing a tool that aims to enhance crowdworkers' experiences by incorporating cultural considerations.