Deep Learning
A Bayesian-inspired, deep learning, semi-supervised domain adaptation technique for land cover mapping
Lucas, Benjamin, Pelletier, Charlotte, Schmidt, Daniel, Webb, Geoffrey I., Petitjean, François
Land cover maps are a vital input variable to many types of environmental research and management. While they can be produced automatically by machine learning techniques, these techniques require substantial training data to achieve high levels of accuracy, which are not always available. One technique researchers use when labelled training data are scarce is domain adaptation (DA) -- where data from an alternate region, known as the source domain, are used to train a classifier and this model is adapted to map the study region, or target domain. The scenario we address in this paper is known as semi-supervised DA, where some labelled samples are available in the target domain. In this paper we present Sourcerer, a Bayesian-inspired, deep learning-based, semi-supervised DA technique for producing land cover maps from SITS data. The technique takes a convolutional neural network trained on a source domain and then trains further on the available target domain with a novel regularizer applied to the model weights. The regularizer adjusts the degree to which the model is modified to fit the target data, limiting the degree of change when the target data are few in number and increasing it as target data quantity increases. Our experiments on Sentinel-2 time series images compare Sourcerer with two state-of-the-art semi-supervised domain adaptation techniques and four baseline models. We show that on two different source-target domain pairings Sourcerer outperforms all other methods for any quantity of labelled target data available. In fact, the results on the more difficult target domain show that the starting accuracy of Sourcerer (when no labelled target data are available), 74.2%, is greater than the next-best state-of-the-art method trained on 20,000 labelled target instances.
Classification of Infant Crying in Real-World Home Environments Using Deep Learning
Yao, Xuewen, Micheletti, Megan, Johnson, Mckensey, de Barbaro, Kaya
In the domain of social signal processing, audio recognition is a promising avenue for accessing daily behaviors that contribute to health and well-being. However, despite advances in mobile computing and machine learning, audio behavior detection models are largely constrained to data collected in controlled settings, such as call centers. This is problematic as it means their performance is unlikely to generalize to real-world applications. In the current paper, we present a model combining deep spectrum and acoustic features to detect and classify infant distress vocalizations from 24 hour, continuous, raw real-world data collected via a wearable audio recorder. Our model dramatically outperforms infant distress detection models trained and tested on equivalent real-world datasets. In particular, our model has an F1 score of 0.597 relative to F1 scores of 0.166 and 0.26 achieved by state-of-practice and state-of-the-art real-world infant distress classifiers, respectively. We end by discussing what may have facilitated this massive gain in accuracy, including using supervised deep spectrum features and the fact that we collected and annotated a massive dataset of 780 hours of real-world audio data with over 25 hours of labelled distress.
Using Computer Vision to enhance Safety of Workforce in Manufacturing in a Post COVID World
Khandelwal, Prateek, Khandelwal, Anuj, Agarwal, Snigdha, Thomas, Deep, Xavier, Naveen, Raghuraman, Arun
The COVID-19 pandemic forced governments across the world to impose lockdowns to prevent virus transmissions. This resulted in the shutdown of all economic activity and accordingly the production at manufacturing plants across most sectors was halted. While there is an urgency to resume production, there is an even greater need to ensure the safety of the workforce at the plant site. Reports indicate that maintaining social distancing and wearing face masks while at work clearly reduces the risk of transmission. We decided to use computer vision on CCTV feeds to monitor worker activity and detect violations which trigger real time voice alerts on the shop floor. This paper describes an efficient and economic approach of using AI to create a safe environment in a manufacturing setup. We demonstrate our approach to build a robust social distancing measurement algorithm using a mix of modern-day deep learning and classic projective geometry techniques. We have deployed our solution at manufacturing plants across the Aditya Birla Group (ABG). We have also described our face mask detection approach which provides a high accuracy across a range of customized masks.
Hedging with Neural Networks
We study neural networks as nonparametric estimation tools for the hedging of options. To this end, we design a network, named HedgeNet, that directly outputs a hedging strategy. This network is trained to minimise the hedging error instead of the pricing error. Applied to end-of-day and tick prices of S&P 500 and Euro Stoxx 50 options, the network is able to reduce the mean squared hedging error of the Black-Scholes benchmark significantly. We illustrate, however, that a similar benefit arises by simple linear regressions that incorporate the leverage effect. Finally, we show how a faulty training/test data split, possibly along with an additional 'tagging' of data, leads to a significant overestimation of the outperformance of neural networks.
DJEnsemble: On the Selection of a Disjoint Ensemble of Deep Learning Black-Box Spatio-temporal Models
Souto, Yania Molina, Pereira, Rafael, Zorrilla, Rocío, Chaves, Anderson, Tsan, Brian, Rusu, Florin, Ogasawara, Eduardo, Ziviani, Artur, Porto, Fabio
In this paper, we present a cost-based approach for the automatic selection and allocation of a disjoint ensemble of black-box predictors to answer predictive spatio-temporal queries. Our approach is divided into two parts -- offline and online. During the offline part, we preprocess the predictive domain data -- transforming it into a regular grid -- and the black-box models -- computing their spatio-temporal learning function. In the online part, we compute a DJEnsemble plan which minimizes a multivariate cost function based on estimates for the prediction error and the execution cost -- producing a model spatial allocation matrix -- and run the optimal ensemble plan. We conduct a set of extensive experiments that evaluate the DJEnsemble approach and highlight its efficiency. We show that our cost model produces plans with performance close to the actual best plan. When compared against the traditional ensemble approach, DJEnsemble achieves up to $4X$ improvement in execution time and almost $9X$ improvement in prediction accuracy. To the best of our knowledge, this is the first work to solve the problem of optimizing the allocation of black-box models to answer predictive spatio-temporal queries.
Stanford CS224N: NLP with Deep Learning Winter 2019 Lecture 1 – Introduction and Word Vectors
Take an adapted version of this course as part of the Stanford Artificial Intelligence Professional Program. Professor Christopher Manning Thomas M. Siebel Professor in Machine Learning, Professor of Linguistics and of Computer Science Director, Stanford Artificial Intelligence Laboratory (SAIL) To follow along with the course schedule and syllabus, visit: http://web.stanford.edu/class/cs224n/... To get the latest news on Stanford's upcoming professional programs in Artificial Intelligence, visit: http://learn.stanford.edu/AI.html To view all online courses and programs offered by Stanford, visit: http://online.stanford.edu
Lecture 8: Recurrent Neural Networks and Language Models
Lecture 8 covers traditional language models, RNNs, and RNN language models. Also reviewed are important training problems and tricks, RNNs for other sequence tasks, and bidirectional and deep RNNs. This lecture series provides a thorough introduction to the cutting-edge research in deep learning applied to NLP, an approach that has recently obtained very high performance across many different NLP tasks including question answering and machine translation. It emphasizes how to implement, train, debug, visualize, and design neural network models, covering the main technologies of word vectors, feed-forward models, recurrent neural networks, recursive neural networks, convolutional neural networks, and recent models involving a memory component. For additional learning opportunities please visit: http://stanfordonline.stanford.edu/
Artificial Intelligence : Best Human Practices and Uses SaveDelete
Artificial Intelligence …. world's tech giants from Amazon to Alibaba, are in a race to become the world's leaders. The companies are AI trailblazers, embracing AI to next-level products and services. Here are some of the best examples of how these companies are using artificial intelligence in practice. Alphabet, Google's parent company and Waymo, self-driving technology division, started as a project at Google. Waymo wishes to bring self-driving technology to the world, today, to move people around and reduce accidents and crashes.
Nomics Machine-Learning Tool Offers 7-Day Price Forecast on Top 100 Cryptos
Data provider Nomics is using machine learning to predict the future prices of cryptocurrencies like bitcoin. Launched Thursday, the 7-Day Asset Price Prediction feed will give an outlook on future crypto prices based on purpose-built algorithms and the firm's API, Nomics CEO Clay Collins told CoinDesk in an interview. "There are a lot of poor signals out there that are getting a lot of clicks and we thought we could do a net positive for the space by just leveling up the quality of predictions," Collins said. The Nomics forecaster isn't a standalone, investment-grade product, Collins added, but can help inform crypto investors based on curated exchange data. The free tool currently lists 100 of the top cryptocurrencies by market cap.
What is computer vision?
If I asked you to name the objects in the picture below, you would probably come up with a list of words such as "tablecloth, basket, grass, boy, girl, man, woman, orange juice bottle, tomatoes, lettuce, disposable plates…" without thinking twice. Now, if I told you to describe the picture below, you would probably say, "It's the picture of a family picnic" again without giving it a second thought. Those are two very easy tasks that any person with below-average intelligence and above the age of six or seven could accomplish. However, in the background, a very complicated process takes place. The human vision is a very intricate piece of organic technology that involves our eyes and visual cortex, but also takes into account our mental models of objects, our abstract understanding of concepts and our personal experiences through billions and trillions of interactions we've made with the world in our lives. Digital equipment can capture images at resolutions and with detail that far surpasses the human vision system.