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How Scientists Are Using AI and Data Science Against COVID-19

#artificialintelligence

In a new study in China, a deep learning model detected COVID19 caused pneumonia from CT scans with comparable performance to expert radiologists. CT is the preferred imaging method for evaluating lung infection, assessing progression, and determining treatment options for patients with pneumonia caused by COVID19. In this study, radiologists used AI to help them evaluate the progression of disease, and with the assistance of this model, radiologists' read time decreased by 65%. The model achieved a per-patient sensitivity of 100% and accuracy of 95.24%. This AI could help improve the efficiency of evaluation and diagnosis especially if the number of people with the virus increases. This article is a preprint and has not been peer-reviewed. This paper reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice. Harvard Medical School students have created a COVID19 curriculum. It includes information about epidemiology, clinical management, testing, treatment, vaccine development, and communication. Each section was reviewed by at least two Harvard Medical School faculty experts. Many modules reference supplemental resources that may be worth accessing in the future and to find the most current statistics of the pandemic. Also included are one-page summaries of each module's key takeaways. COVID19 testing in South Korea is free and convenient and over 250,000 people have already been tested. The South Korean data is valuable because they are testing people who have symptoms and people who have no symptoms. This is unusual because most countries are only testing people who are sick to confirm that they have the virus. South Korea is testing everyone, including asymptomatic people, as a public health measure so that anyone who has the virus can isolate even if they don't feel sick. In most countries asymptomatic people are not tested for COVID19. For example Italy is only testing symptomatic people, whereas South Korea tests everyone and picks up more mild cases.


From Artificial Neural Networks to Deep Learning for Music Generation -- History, Concepts and Trends

arXiv.org Machine Learning

The current tsunami of deep learning (the hyper-vitamined return of artificial neural networks) applies not only to traditional statistical machine learning tasks: prediction and classification (e.g., for weather prediction and pattern recognition), but has already conquered other areas, such as translation. A growing area of application is the generation of creative content: in particular the case of music, the topic of this paper. The motivation is in using the capacity of modern deep learning techniques to automatically learn musical styles from arbitrary musical corpora and then to generate musical samples from the estimated distribution, with some degree of control over the generation. This article provides a survey of music generation based on deep learning techniques. After a short introduction to the topic illustrated by a recent exemple, the article analyses some early works from the late 1980s using artificial neural networks for music generation and how their pioneering contributions foreshadowed current techniques. Then, we introduce some conceptual framework to analyze the various concepts and dimensions involved. Various examples of recent systems are introduced and analyzed to illustrate the variety of concerns and of techniques.


A survey of bias in Machine Learning through the prism of Statistical Parity for the Adult Data Set

arXiv.org Machine Learning

Applications based on Machine Learning models have now become an indispensable part of the everyday life and the professional world. A critical question then recently arised among the population: Do algorithmic decisions convey any type of discrimination against specific groups of population or minorities? In this paper, we show the importance of understanding how a bias can be introduced into automatic decisions. We first present a mathematical framework for the fair learning problem, specifically in the binary classification setting. We then propose to quantify the presence of bias by using the standard Disparate Impact index on the real and well-known Adult income data set. Finally, we check the performance of different approaches aiming to reduce the bias in binary classification outcomes. Importantly, we show that some intuitive methods are ineffective. This sheds light on the fact trying to make fair machine learning models may be a particularly challenging task, in particular when the training observations contain a bias.


A Norm Emergence Framework for Normative MAS -- Position Paper

arXiv.org Artificial Intelligence

Norm emergence is typically studied in the context of multiagent systems (MAS) where norms are implicit, and participating agents use simplistic decision-making mechanisms. These implicit norms are usually unconsciously shared and adopted through agent interaction. A norm is deemed to have emerged when a threshold or predetermined percentage of agents follow the "norm". Conversely, in normative MAS, norms are typically explicit and agents deliberately share norms through communication or are informed about norms by an authority, following which an agent decides whether to adopt the norm or not. The decision to adopt a norm by the agent can happen immediately after recognition or when an applicable situation arises. In this paper, we make the case that, similarly, a norm has emerged in a normative MAS when a percentage of agents adopt the norm. Furthermore, we posit that agents themselves can and should be involved in norm synthesis, and hence influence the norms governing the MAS, in line with Ostrom's eight principles. Consequently, we put forward a framework for the emergence of norms within a normative MAS, that allows participating agents to propose/request changes to the normative system, while special-purpose synthesizer agents formulate new norms or revisions in response to these requests. Synthesizers must collectively agree that the new norm or norm revision should proceed, and then finally be approved by an "Oracle". The normative system is then modified to incorporate the norm.


Emotional Video to Audio Transformation Using Deep Recurrent Neural Networks and a Neuro-Fuzzy System

arXiv.org Machine Learning

Generating music with emotion similar to that of an input video is a very relevant issue nowadays. Video content creators and automatic movie directors benefit from maintaining their viewers engaged, which can be facilitated by producing novel material eliciting stronger emotions in them. Moreover, there's currently a demand for more empathetic computers to aid humans in applications such as augmenting the perception ability of visually and/or hearing impaired people. Current approaches overlook the video's emotional characteristics in the music generation step, only consider static images instead of videos, are unable to generate novel music, and require a high level of human effort and skills. In this study, we propose a novel hybrid deep neural network that uses an Adaptive Neuro-Fuzzy Inference System to predict a video's emotion from its visual features and a deep Long Short-Term Memory Recurrent Neural Network to generate its corresponding audio signals with similar emotional inkling. The former is able to appropriately model emotions due to its fuzzy properties, and the latter is able to model data with dynamic time properties well due to the availability of the previous hidden state information. The novelty of our proposed method lies in the extraction of visual emotional features in order to transform them into audio signals with corresponding emotional aspects for users. Quantitative experiments show low mean absolute errors of 0.217 and 0.255 in the Lindsey and DEAP datasets respectively, and similar global features in the spectrograms. This indicates that our model is able to appropriately perform domain transformation between visual and audio features. Based on experimental results, our model can effectively generate audio that matches the scene eliciting a similar emotion from the viewer in both datasets, and music generated by our model is also chosen more often.


Predicting Unplanned Readmissions with Highly Unstructured Data

arXiv.org Machine Learning

Deep learning techniques have been successfully applied to predict unplanned readmissions of patients in medical centers. The training data for these models is usually based on historical medical records that contain a significant amount of free-text from admission reports, referrals, exam notes, etc. Most of the models proposed so far are tailored to English text data and assume that electronic medical records follow standards common in developed countries. These two characteristics make them difficult to apply in developing countries that do not necessarily follow international standards for registering patient information, or that store text information in languages other than English. In this paper we propose a deep learning architecture for predicting unplanned readmissions that consumes data that is significantly less structured compared with previous models in the literature. We use it to present the first results for this task in a large clinical dataset that mainly contains Spanish text data. The dataset is composed of almost 10 years of records in a Chilean medical center. On this dataset, our model achieves results that are comparable to some of the most recent results obtained in US medical centers for the same task (0.76 AUROC).


Differential 3D Facial Recognition: Adding 3D to Your State-of-the-Art 2D Method

arXiv.org Machine Learning

Active illumination is a prominent complement to enhance 2D face recognition and make it more robust, e.g., to spoofing attacks and low-light conditions. In the present work we show that it is possible to adopt active illumination to enhance state-of-the-art 2D face recognition approaches with 3D features, while bypassing the complicated task of 3D reconstruction. The key idea is to project over the test face a high spatial frequency pattern, which allows us to simultaneously recover real 3D information plus a standard 2D facial image. Therefore, state-of-the-art 2D face recognition solution can be transparently applied, while from the high frequency component of the input image, complementary 3D facial features are extracted. Experimental results on ND-2006 dataset show that the proposed ideas can significantly boost face recognition performance and dramatically improve the robustness to spoofing attacks.


Predicting rice blast disease: machine learning versus process based models

arXiv.org Machine Learning

Rice is the second most important cereal crop worldwide, and the first in terms of number of people who depend on it as a major staple food. Rice blast disease is the most important biotic constraint of rice cultivation causing each year millions of dollars of losses. Despite the efforts for breeding new resistant varieties, agricultural practices and chemical control are still the most important methods for disease management. Thus, rice blast forecasting is a primary tool to support rice growers in controlling the disease. In this study, we compared four models for predicting rice blast disease, two operational process-based models (Yoshino and WARM) and two approaches based on machine learning algorithms (M5Rules and RNN), the former inducing a rule-based model and the latter building a neural network. In situ telemetry is important to obtain quality in-field data for predictive models and this was a key aspect of the RICE-GUARD project on which this study is based. According to the authors, this is the first time process-based and machine learning modelling approaches for supporting plant disease management are compared.


CPPN2GAN: Combining Compositional Pattern Producing Networks and GANs for Large-scale Pattern Generation

arXiv.org Artificial Intelligence

Generative Adversarial Networks (GANs) are proving to be a powerful indirect genotype-to-phenotype mapping for evolutionary search, but they have limitations. In particular, GAN output does not scale to arbitrary dimensions, and there is no obvious way of combining multiple GAN outputs into a cohesive whole, which would be useful in many areas, such as the generation of video game levels. Game levels often consist of several segments, sometimes repeated directly or with variation, organized into an engaging pattern. Such patterns can be produced with Compositional Pattern Producing Networks (CPPNs). Specifically, a CPPN can define latent vector GAN inputs as a function of geometry, which provides a way to organize level segments output by a GAN into a complete level. This new CPPN2GAN approach is validated in both Super Mario Bros. and The Legend of Zelda. Specifically, divergent search via MAP-Elites demonstrates that CPPN2GAN can better cover the space of possible levels. The layouts of the resulting levels are also more cohesive and aesthetically consistent.


Predicting Chaos: Story Behind One Of Israel's Most Advanced Fintech AI Start-Ups

#artificialintelligence

And while that was happening, the financial sector was also taking note. Among the many boons of AI tech for finance is the practice called algorithmic trading: the idea that an advanced AI may be able to assist the investors by predicting the market dynamics with enough precision to make consistent profit. And while many advanced machine learning models developed for this purpose stay outside the reach of the general public, others are eager to make AI-driven trading available to a broader audience. One of the leaders in this sphere is the Israel-based company with an ambitious name I Know First. With its powerful cloud-based AI capable of predicting the price dynamics for more than 10,000 financial instruments, including stock ideas, ETFs, world indices, commodities and currencies, it offers its forecasts to private and institutional investors alike.