Deep Learning
Why you shouldn't be a data science generalist – Towards Data Science
I work at a data science mentorship startup, and I've found there's a single piece of advice that I catch myself giving over and over again to aspiring mentees. And it's really not what I would have expected it to be. Rather than suggesting a new library or tool, or some resume hack, I find myself recommending that they first think about what kind of data scientist they want to be. The reason this is crucial is that data science isn't a single, well-defined field, and companies don't hire generic, jack-of-all-trades "data scientists", but rather individuals with very specialized skill sets. To see why, just imagine that you're a company trying to hire a data scientist. You almost certainly have a fairly well-defined problem in mind that you need help with, and that problem is going to require some fairly specific technical know-how and subject matter expertise.
On Device AI: The next 'SMART' thing. – The Startup – Medium
AI is a superset that encompasses both Machine learning and Deep learning. Francois Chollet in his book'Deep Learning with Python' describes Artificial Intelligence as the ability to automate intellectual tasks usually performed by humans. However for any machine to exhibit Artificial Intelligence, it needs to learn from the past experiences which come in the form of datasets called training data. These learnings are then used to predict results for unseen test data. So, inherently, AI is a broader term, but for any machine to exhibit Artificial Intelligence, they need to be trained using Machine Learning Algorithms. Deep learning is a subfield of Machine learning which is a new a new take on learning representations from data that emphasizes learning successive layers of increasingly meaningful representations.
Why Elon Musk fears artificial intelligence
Elon Musk is usually far from a technological pessimist. From electric cars to Mars colonies, he's made his name by insisting that the future can get here faster. But when it comes to artificial intelligence, he sounds very different. Speaking at MIT in 2014, he called AI humanity's "biggest existential threat" and compared it to "summoning the demon." He reiterated those fears in an interview published Friday with Recode's Kara Swisher, though with a little less apocalyptic rhetoric.
An Introduction to AI
I am Imtiaz Adam, and this article is an introduction to AI key terminologies and methodologies on behalf of myself and DLS (www.dls.ltd). AI deals with the area of developing computing systems which are capable of performing tasks that humans are very good at, for example recognising objects, recognising and making sense of speech, and decision making in a constrained environment. Narrow AI: the field of AI where the machine is designed to perform a single task and the machine gets very good at performing that particular task. However, once the machine is trained, it does not generalise to unseen domains. This is the form of AI that we have today, for example Google Translate.
Learning to Defense by Learning to Attack
Chen, Zhehui, Jiang, Haoming, Dai, Bo, Zhao, Tuo
Adversarial training provides a principled approach for training robust neural networks. From an optimization perspective, the adversarial training is essentially solving a minmax robust optimization problem. The outer minimization is trying to learn a robust classifier, while the inner maximization is trying to generate adversarial samples. Unfortunately, such a minmax problem is very difficult to solve due to the lack of convex-concave structure. This work proposes a new adversarial training method based on a general learning-to-learn framework. Specifically, instead of applying the existing hand-design algorithms for the inner problem, we learn an optimizer, which is parametrized as a convolutional neural network. At the same time, a robust classifier is learned to defense the adversarial attack generated by the learned optimizer. Our experiments demonstrate that our proposed method significantly outperforms existing adversarial training methods on CIFAR-10 and CIFAR-100 datasets.
Nonlinear Collaborative Scheme for Deep Neural Networks
Zhen, Hui-Ling, Lin, Xi, Tang, Alan Z., Li, Zhenhua, Zhang, Qingfu, Kwong, Sam
Conventional research attributes the improvements of generalization ability of deep neural networks either to powerful optimizers or the new network design. Different from them, in this paper, we aim to link the generalization ability of a deep network to optimizing a new objective function. To this end, we propose a \textit{nonlinear collaborative scheme} for deep network training, with the key technique as combining different loss functions in a nonlinear manner. We find that after adaptively tuning the weights of different loss functions, the proposed objective function can efficiently guide the optimization process. What is more, we demonstrate that, from the mathematical perspective, the nonlinear collaborative scheme can lead to (i) smaller KL divergence with respect to optimal solutions; (ii) data-driven stochastic gradient descent; (iii) tighter PAC-Bayes bound. We also prove that its advantage can be strengthened by nonlinearity increasing. To some extent, we bridge the gap between learning (i.e., minimizing the new objective function) and generalization (i.e., minimizing a PAC-Bayes bound) in the new scheme. We also interpret our findings through the experiments on Residual Networks and DenseNet, showing that our new scheme performs superior to single-loss and multi-loss schemes no matter with randomization or not.
Adversarial Gain
Henderson, Peter, Sinha, Koustuv, Ke, Rosemary Nan, Pineau, Joelle
Adversarial examples can be defined as inputs to a model which induce a mistake - where the model output is different than that of an oracle, perhaps in surprising or malicious ways. Original models of adversarial attacks are primarily studied in the context of classification and computer vision tasks. While several attacks have been proposed in natural language processing (NLP) settings, they often vary in defining the parameters of an attack and what a successful attack would look like. The goal of this work is to propose a unifying model of adversarial examples suitable for NLP tasks in both generative and classification settings. We define the notion of adversarial gain: based in control theory, it is a measure of the change in the output of a system relative to the perturbation of the input (caused by the so-called adversary) presented to the learner. This definition, as we show, can be used under different feature spaces and distance conditions to determine attack or defense effectiveness across different intuitive manifolds. This notion of adversarial gain not only provides a useful way for evaluating adversaries and defenses, but can act as a building block for future work in robustness under adversaries due to its rooted nature in stability and manifold theory.
Radius-margin bounds for deep neural networks
Sharma, Mayank, Jayadeva, null, Soman, Sumit
Explaining the unreasonable effectiveness of deep learning has eluded researchers around the globe. Various authors have described multiple metrics to evaluate the capacity of deep architectures. In this paper, we allude to the radius margin bounds described for a support vector machine (SVM) with hinge loss, apply the same to the deep feed-forward architectures and derive the Vapnik-Chervonenkis (VC) bounds which are different from the earlier bounds proposed in terms of number of weights of the network. In doing so, we also relate the effectiveness of techniques like Dropout and Dropconnect in bringing down the capacity of the network. Finally, we describe the effect of maximizing the input as well as the output margin to achieve an input noise-robust deep architecture.
Strategies for Training Stain Invariant CNNs
Lampert, Thomas, Merveille, Odyssée, Schmitz, Jessica, Forestier, Germain, Feuerhake, Friedrich, Wemmert, Cédric
An important part of Digital Pathology is the analysis of multiple digitised whole slide images from differently stained tissue sections. It is common practice to mount consecutive sections containing corresponding microscopic structures on glass slides, and to stain them differently to highlight specific tissue components. These multiple staining modalities result in very different images but include a significant amount of consistent image information. Deep learning approaches have recently been proposed to analyse these images in order to automatically identify objects of interest for pathologists. These supervised approaches require a vast amount of annotations, which are difficult and expensive to acquire---a problem that is multiplied with multiple stainings. This article presents several training strategies that make progress towards stain invariant networks. By training the network on one commonly used staining modality and applying it to images that include corresponding but differently stained tissue structures, the presented unsupervised strategies demonstrate significant improvements over standard training strategies.
Theoretical Linear Convergence of Unfolded ISTA and its Practical Weights and Thresholds
Chen, Xiaohan, Liu, Jialin, Wang, Zhangyang, Yin, Wotao
In recent years, unfolding iterative algorithms as neural networks has become an empirical success in solving sparse recovery problems. However, its theoretical understanding is still immature, which prevents us from fully utilizing the power of neural networks. In this work, we study unfolded ISTA (Iterative Shrinkage Thresholding Algorithm) for sparse signal recovery. We introduce a weight structure that is necessary for asymptotic convergence to the true sparse signal. With this structure, unfolded ISTA can attain a linear convergence, which is better than the sublinear convergence of ISTA/FISTA in general cases. Furthermore, we propose to incorporate thresholding in the network to perform support selection, which is easy to implement and able to boost the convergence rate both theoretically and empirically. Extensive simulations, including sparse vector recovery and a compressive sensing experiment on real image data, corroborate our theoretical results and demonstrate their practical usefulness.