Deep Learning
Derivation of Information-Theoretically Optimal Adversarial Attacks with Applications to Robust Machine Learning
Yi, Jirong, Mudumbai, Raghu, Xu, Weiyu
We consider the theoretical problem of designing an optimal adversarial attack on a decision system that maximally degrades the achievable performance of the system as measured by the mutual information between the degraded signal and the label of interest. This problem is motivated by the existence of adversarial examples for machine learning classifiers. By adopting an information theoretic perspective, we seek to identify conditions under which adversarial vulnerability is unavoidable i.e. even optimally designed classifiers will be vulnerable to small adversarial perturbations. We present derivations of the optimal adversarial attacks for discrete and continuous signals of interest, i.e., finding the optimal perturbation distributions to minimize the mutual information between the degraded signal and a signal following a continuous or discrete distribution. In addition, we show that it is much harder to achieve adversarial attacks for minimizing mutual information when multiple redundant copies of the input signal are available. This provides additional support to the recently proposed ``feature compression" hypothesis as an explanation for the adversarial vulnerability of deep learning classifiers. We also report on results from computational experiments to illustrate our theoretical results.
Stochastic Normalized Gradient Descent with Momentum for Large Batch Training
Zhao, Shen-Yi, Xie, Yin-Peng, Li, Wu-Jun
Stochastic gradient descent (SGD) and its variants have been the dominating optimization methods in machine learning. Compared with small batch training, SGD with large batch training can better utilize the computational power of current multi-core systems like GPUs and can reduce the number of communication rounds in distributed training. Hence, SGD with large batch training has attracted more and more attention. However, existing empirical results show that large batch training typically leads to a drop of generalization accuracy. As a result, large batch training has also become a challenging topic. In this paper, we propose a novel method, called stochastic normalized gradient descent with momentum (SNGM), for large batch training. We theoretically prove that compared to momentum SGD (MSGD) which is one of the most widely used variants of SGD, SNGM can adopt a larger batch size to converge to the $\epsilon$-stationary point with the same computation complexity (total number of gradient computation). Empirical results on deep learning also show that SNGM can achieve the state-of-the-art accuracy with a large batch size.
Emotion Correlation Mining Through Deep Learning Models on Natural Language Text
Wang, Xinzhi, Kou, Luyao, Sugumaran, Vijayan, Luo, Xiangfeng, Zhang, Hui
Emotion analysis has been attracting researchers' attention. Most previous works in the artificial intelligence field focus on recognizing emotion rather than mining the reason why emotions are not or wrongly recognized. Correlation among emotions contributes to the failure of emotion recognition. In this paper, we try to fill the gap between emotion recognition and emotion correlation mining through natural language text from web news. Correlation among emotions, expressed as the confusion and evolution of emotion, is primarily caused by human emotion cognitive bias. To mine emotion correlation from emotion recognition through text, three kinds of features and two deep neural network models are presented. The emotion confusion law is extracted through orthogonal basis. The emotion evolution law is evaluated from three perspectives, one-step shift, limited-step shifts, and shortest path transfer. The method is validated using three datasets-the titles, the bodies, and the comments of news articles, covering both objective and subjective texts in varying lengths (long and short). The experimental results show that, in subjective comments, emotions are easily mistaken as anger. Comments tend to arouse emotion circulations of love-anger and sadness-anger. In objective news, it is easy to recognize text emotion as love and cause fear-joy circulation. That means, journalists may try to attract attention using fear and joy words but arouse the emotion love instead; After news release, netizens generate emotional comments to express their intense emotions, i.e., anger, sadness, and love. These findings could provide insights for applications regarding affective interaction such as network public sentiment, social media communication, and human-computer interaction.
Dreaming: Model-based Reinforcement Learning by Latent Imagination without Reconstruction
Okada, Masashi, Taniguchi, Tadahiro
In the present paper, we propose a decoder-free extension of Dreamer, a leading model-based reinforcement learning (MBRL) method from pixels. Dreamer is a sample- and cost-efficient solution to robot learning, as it is used to train latent state-space models based on a variational autoencoder and to conduct policy optimization by latent trajectory imagination. However, this autoencoding based approach often causes object vanishing, in which the autoencoder fails to perceives key objects for solving control tasks, and thus significantly limiting Dreamer's potential. This work aims to relieve this Dreamer's bottleneck and enhance its performance by means of removing the decoder. For this purpose, we firstly derive a likelihood-free and InfoMax objective of contrastive learning from the evidence lower bound of Dreamer. Secondly, we incorporate two components, (i) independent linear dynamics and (ii) the random crop data augmentation, to the learning scheme so as to improve the training performance. In comparison to Dreamer and other recent model-free reinforcement learning methods, our newly devised Dreamer with InfoMax and without generative decoder (Dreaming) achieves the best scores on 5 difficult simulated robotics tasks, in which Dreamer suffers from object vanishing.
DeepMind's Newest AI Programs Itself to Make All the Right Decisions
Three main deep learning approaches are supervised, unsupervised, and reinforcement learning. The first two consume huge amounts of data (like images or articles), look for patterns in the data, and use those patterns to inform actions (like identifying an image of a cat). To us, this is a pretty alien way to learn about the world. Not only would it be mind-numbingly dull to review millions of cat images, it'd take us years or more to do what these programs do in hours or days. And of course, we can learn what a cat looks like from just a few examples.
Elon Musk says he's terrified of AI taking over the world and most scared of Google's DeepMind AI project
Elon Musk has been sounding the alarm about the potentially dangerous, species-ending future of artificial intelligence for years. In 2016, the billionaire said human beings could become the equivalent of "house cats" to new AI overlords. He has since repeatedly called for regulation and caution when it comes to new AI technology. But of all the various AI projects in the works, none has Musk more worried than Google's DeepMind. "Just the nature of the AI that they're building is one that crushes all humans at all games," Musk told The New York Times in an interview.
Looking into the black box
Deep learning systems are revolutionizing technology around us, from voice recognition that pairs you with your phone to autonomous vehicles that are increasingly able to see and recognize obstacles ahead. But much of this success involves trial and error when it comes to the deep learning networks themselves. A group of MIT researchers recently reviewed their contributions to a better theoretical understanding of deep learning networks, providing direction for the field moving forward. "Deep learning was in some ways an accidental discovery," explains Tommy Poggio, investigator at the McGovern Institute for Brain Research, director of the Center for Brains, Minds, and Machines (CBMM), and the Eugene McDermott Professor in Brain and Cognitive Sciences. "We still do not understand why it works. A theoretical framework is taking form, and I believe that we are now close to a satisfactory theory. It is time to stand back and review recent insights."
Deep learningโbased methods for individual recognition in small birds
Individual identification is a crucial step to answer many questions in evolutionary biology and is mostly performed by marking animals with tags. Such methods are wellโestablished, but often make data collection and analyses timeโconsuming, or limit the contexts in which data can be collected. Recent computational advances, specifically deep learning, can help overcome the limitations of collecting largeโscale data across contexts. However, one of the bottlenecks preventing the application of deep learning for individual identification is the need to collect and identify hundreds to thousands of individually labelled pictures to train convolutional neural networks (CNNs). Here we describe procedures for automating the collection of training data, generating training datasets, and training CNNs to allow identification of individual birds.
OpenAI's Text Generator Is Going Commercial
Last spring, artificial intelligence research institute OpenAI said it had made software so good at generating text--including fake news articles--that it was too dangerous to release. That line in the sand was soon erased when two recent master's grads recreated the software and OpenAI released the original, saying awareness of the risks had grown and it hadn't seen evidence of misuse. Now the lab is back with a more powerful text generator and a new pitch: Pay us to put it to work in your business. Thursday, OpenAI launched a cloud service that a handful of companies are already using to improve search or provide feedback on answers to math problems. OpenAI was founded as a nonprofit in 2015 by Elon Musk and other Silicon Valley notables to ensure that future superhuman AI was a benign force.
Examples of Artificial Intelligence
Artificial intelligence, powered by deep-learning algorithms, is already in use in healthcare. Specifically, AI's imaging capabilities are promising for cancer identification and screening, including breast cancer. Artificial intelligence is also used to predict the development of diseases across a healthcare network. A group at Mount Sinai used deep learning-based AI algorithms to predict the development of diseases with 94% accuracy, including cancers of liver, rectum, and prostate. Did you know The World Bee Project?