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MANTIS at TSAR-2022 Shared Task: Improved Unsupervised Lexical Simplification with Pretrained Encoders

arXiv.org Artificial Intelligence

In this paper we present our contribution to the TSAR-2022 Shared Task on Lexical Simplification of the EMNLP 2022 Workshop on Text Simplification, Accessibility, and Readability. Our approach builds on and extends the unsupervised lexical simplification system with pretrained encoders (LSBert) system in the following ways: For the subtask of simplification candidate selection, it utilizes a RoBERTa transformer language model and expands the size of the generated candidate list. For subsequent substitution ranking, it introduces a new feature weighting scheme and adopts a candidate filtering method based on textual entailment to maximize semantic similarity between the target word and its simplification. Our best-performing system improves LSBert by 5.9% accuracy and achieves second place out of 33 ranked solutions.


GD-VAEs: Geometric Dynamic Variational Autoencoders for Learning Nonlinear Dynamics and Dimension Reductions

arXiv.org Artificial Intelligence

We develop data-driven methods incorporating geometric and topological information to learn parsimonious representations of nonlinear dynamics from observations. We develop approaches for learning nonlinear state space models of the dynamics for general manifold latent spaces using training strategies related to Variational Autoencoders (VAEs). Our methods are referred to as Geometric Dynamic (GD) Variational Autoencoders (GD-VAEs). We learn encoders and decoders for the system states and evolution based on deep neural network architectures that include general Multilayer Perceptrons (MLPs), Convolutional Neural Networks (CNNs), and Transpose CNNs (T-CNNs). Motivated by problems arising in parameterized PDEs and physics, we investigate the performance of our methods on tasks for learning low dimensional representations of the nonlinear Burgers equations, constrained mechanical systems, and spatial fields of reaction-diffusion systems. GD-VAEs provide methods for obtaining representations for use in diverse learning tasks involving dynamics.


Almost Cost-Free Communication in Federated Best Arm Identification

arXiv.org Artificial Intelligence

We study the problem of best arm identification in a federated learning multi-armed bandit setup with a central server and multiple clients. Each client is associated with a multi-armed bandit in which each arm yields {\em i.i.d.}\ rewards following a Gaussian distribution with an unknown mean and known variance. The set of arms is assumed to be the same at all the clients. We define two notions of best arm -- local and global. The local best arm at a client is the arm with the largest mean among the arms local to the client, whereas the global best arm is the arm with the largest average mean across all the clients. We assume that each client can only observe the rewards from its local arms and thereby estimate its local best arm. The clients communicate with a central server on uplinks that entail a cost of $C\ge0$ units per usage per uplink. The global best arm is estimated at the server. The goal is to identify the local best arms and the global best arm with minimal total cost, defined as the sum of the total number of arm selections at all the clients and the total communication cost, subject to an upper bound on the error probability. We propose a novel algorithm {\sc FedElim} that is based on successive elimination and communicates only in exponential time steps and obtain a high probability instance-dependent upper bound on its total cost. The key takeaway from our paper is that for any $C\geq 0$ and error probabilities sufficiently small, the total number of arm selections (resp.\ the total cost) under {\sc FedElim} is at most~$2$ (resp.~$3$) times the maximum total number of arm selections under its variant that communicates in every time step. Additionally, we show that the latter is optimal in expectation up to a constant factor, thereby demonstrating that communication is almost cost-free in {\sc FedElim}. We numerically validate the efficacy of {\sc FedElim}.


Multimodal CNN Networks for Brain Tumor Segmentation in MRI: A BraTS 2022 Challenge Solution

arXiv.org Artificial Intelligence

Automatic segmentation is essential for the brain tumor diagnosis, disease prognosis, and follow-up therapy of patients with gliomas. Still, accurate detection of gliomas and their sub-regions in multimodal MRI is very challenging due to the variety of scanners and imaging protocols. Over the last years, the BraTS Challenge has provided a large number of multi-institutional MRI scans as a benchmark for glioma segmentation algorithms. This paper describes our contribution to the BraTS 2022 Continuous Evaluation challenge. We propose a new ensemble of multiple deep learning frameworks namely, DeepSeg, nnU-Net, and DeepSCAN for automatic glioma boundaries detection in pre-operative MRI. It is worth noting that our ensemble models took first place in the final evaluation on the BraTS testing dataset with Dice scores of 0.9294, 0.8788, and 0.8803, and Hausdorf distance of 5.23, 13.54, and 12.05, for the whole tumor, tumor core, and enhancing tumor, respectively. Furthermore, the proposed ensemble method ranked first in the final ranking on another unseen test dataset, namely Sub-Saharan Africa dataset, achieving mean Dice scores of 0.9737, 0.9593, and 0.9022, and HD95 of 2.66, 1.72, 3.32 for the whole tumor, tumor core, and enhancing tumor, respectively.


Artificial Intelligence Service Market size was valued at USD 93.5 billion in 2021, growing at a CAGR of 38.1% from 2022 to 2032: Evolve Business Intelligence - Digital Journal

#artificialintelligence

Artificial intelligence (AI), often recognized as machine intelligence, is an area of computer science that emphasizes developing and managing technology that can learn to make choices and can separately carry out transactions on behalf of humans. The banking, financial services, and insurance segments experience substantial expansion during the estimated period. A substantial amount of client data or transaction records are produced owing to the rising digital revolution in banking and the augmented use of mobile payment, real-time money transfers, e-banking, and mobile banking applications. The global Artificial Intelligence Service Market size was valued at USD 93.5 billion in 2021 growing at the CAGR of 38.1% from 2022 to 2032. Evolve Business Intelligence provides an in-dept research study that contains the ability to focus on the major market dynamics in several region across the globe.


The 10 biggest science stories of 2022 – chosen by scientists

The Guardian

The year opened with a bang. The successful film Don't Look Up, in which a comet is found to be on a collision course with Earth, had been released just before Christmas 2021. In the bleak days of post-festive gloom, the news media were on an adrenaline high, chasing any and every story about potential asteroid collisions to cheer us all up. Five asteroids were to pass close to the Earth in January alone! Happily for the health and wellbeing of humanity, none was predicted to come within a whisker of hitting the planet.


GUEST ESSAY: Welcome to the machine -- yes, AI is capable of creative output

#artificialintelligence

Recently I innocently posted online (okay, maybe not so innocently) a few graphic images from a hot and hip open-source AI image generator called Stable Diffusion 2. The reason for this was an ongoing debate I have had for years with an architect friend of mine. My position is that AI will eventually (in our lifetimes) compete successfully with human creativity in essentially every conceivable field. My architect friend, and most people, do not agree. I wanted to show my friend that the AI could create a pleasing, surprising and imaginative graphic for the cover of a hypothetical book on modern architecture, or perhaps a banner ad for an architecture conference. So I typed the following into the text box on the front page of the Stable Diffusion 2 website: "architect imagination, building with clean lines, impressionist".


Africa prepares for age of robots - The Mail & Guardian

#artificialintelligence

The adoption of robotics and artificial intelligence (AI) in Africa received a major boost after Uniccon Group, an Abuja-based tech startup, unveiled the continent's first humanoid robot. Omeife, the 1.8m female human-like robot, is African by design and has Igbo-like physical attributes. The battery-powered robot can speak Igbo, Yoruba, English, French, Swahili, Wazobia, Pidgin, Afrikaans and Arabic with native accents. Uniccon Group chief executive Chuks Ekwueme said: "Omeife also identifies objects and calculates positions and distances of objects." The launch of Omeife comes a few months after Abdul Malik Tejan-Sie, a South African-based Sierra Leonean innovator, presented a prototype of South Africa's first humanoid robot.


Africa prepares for age of robots – The Mail & Guardian

#artificialintelligence

In Nigeria, the National Centre for Artificial Intelligence and Robotics has significantly pushed the country to advance in machine learning, the …


Synthesis and Evaluation of a Domain-specific Large Data Set for Dungeons & Dragons

arXiv.org Artificial Intelligence

This paper introduces the Forgotten Realms Wiki (FRW) data set and domain specific natural language generation using FRW along with related analyses. Forgotten Realms is the de-facto default setting of the popular open ended tabletop fantasy role playing game, Dungeons & Dragons. The data set was extracted from the Forgotten Realms Fandom wiki consisting of more than over 45,200 articles. The FRW data set is constituted of 11 sub-data sets in a number of formats: raw plain text, plain text annotated by article title, directed link graphs, wiki info-boxes annotated by the wiki article title, Poincar\'e embedding of first link graph, multiple Word2Vec and Doc2Vec models of the corpus. This is the first data set of this size for the Dungeons & Dragons domain. We then present a pairwise similarity comparison benchmark which utilizes similarity measures. In addition, we perform D&D domain specific natural language generation using the corpus and evaluate the named entity classification with respect to the lore of Forgotten Realms.