Deep Learning
LocalDrop: A Hybrid Regularization for Deep Neural Networks
Lu, Ziqing, Xu, Chang, Du, Bo, Ishida, Takashi, Zhang, Lefei, Sugiyama, Masashi
Abstract--In neural networks, developing regularization algorithm s to settle overfitting is one of the major study areas. We prop ose a new approach for the regularization of neural networks by th e local Rademacher complexity called LocalDrop. A new regul arization function for both fully-connected networks (FCNs) and conv olutional neural networks (CNNs), including drop rates and weight matrices, has been developed based on the proposed upper bound of the lo cal Rademacher complexity by the strict mathematical deduc tion. The analyses of dropout in FCNs and DropBlock in CNNs with kee p rate matrices in different layers are also included in the c omplexity analyses. With the new regularization function, we establi sh a two-stage procedure to obtain the optimal keep rate matr ix and weight matrix to realize the whole training model. Extensive exper iments have been conducted to demonstrate the effectivenes s of LocalDrop in different models by comparing it with several algorithms and the effects of different hyperparameters on the final per formances. Neural networks have lately shown impressive performance i n sophisticated real-world situations, including image cla ssification [1], object recognition [2] and image captioning [3]. Low, m iddle and high level features are integrated into deep neural netw orks, which are usually trained in an end-to-end manner.
Convolutional Normalization: Improving Deep Convolutional Network Robustness and Training
Liu, Sheng, Li, Xiao, Zhai, Yuexiang, You, Chong, Zhu, Zhihui, Fernandez-Granda, Carlos, Qu, Qing
Normalization techniques have become a basic component in modern convolutional neural networks (ConvNets). In particular, many recent works demonstrate that promoting the orthogonality of the weights helps train deep models and improve robustness. For ConvNets, most existing methods are based on penalizing or normalizing weight matrices derived from concatenating or flattening the convolutional kernels. These methods often destroy or ignore the benign convolutional structure of the kernels; therefore, they are often expensive or impractical for deep ConvNets. In contrast, we introduce a simple and efficient ``convolutional normalization'' method that can fully exploit the convolutional structure in the Fourier domain and serve as a simple plug-and-play module to be conveniently incorporated into any ConvNets. Our method is inspired by recent work on preconditioning methods for convolutional sparse coding and can effectively promote each layer's channel-wise isometry. Furthermore, we show that convolutional normalization can reduce the layerwise spectral norm of the weight matrices and hence improve the Lipschitzness of the network, leading to easier training and improved robustness for deep ConvNets. Applied to classification under noise corruptions and generative adversarial network (GAN), we show that convolutional normalization improves the robustness of common ConvNets such as ResNet and the performance of GAN. We verify our findings via extensive numerical experiments on CIFAR-10, CIFAR-100, and ImageNet.
Scaling up Mean Field Games with Online Mirror Descent
Perolat, Julien, Perrin, Sarah, Elie, Romuald, Lauriรจre, Mathieu, Piliouras, Georgios, Geist, Matthieu, Tuyls, Karl, Pietquin, Olivier
We address scaling up equilibrium computation in Mean Field Games (MFGs) using Online Mirror Descent (OMD). We show that continuous-time OMD provably converges to a Nash equilibrium under a natural and well-motivated set of monotonicity assumptions. This theoretical result nicely extends to multi-population games and to settings involving common noise. A thorough experimental investigation on various single and multi-population MFGs shows that OMD outperforms traditional algorithms such as Fictitious Play (FP). We empirically show that OMD scales up and converges significantly faster than FP by solving, for the first time to our knowledge, examples of MFGs with hundreds of billions states. This study establishes the state-of-the-art for learning in large-scale multi-agent and multi-population games.
A Kinematic Bottleneck Approach For Pose Regression of Flexible Surgical Instruments directly from Images
Sestini, Luca, Rosa, Benoit, De Momi, Elena, Ferrigno, Giancarlo, Padoy, Nicolas
3-D pose estimation of instruments is a crucial step towards automatic scene understanding in robotic minimally invasive surgery. Although robotic systems can potentially directly provide joint values, this information is not commonly exploited inside the operating room, due to its possible unreliability, limited access and the time-consuming calibration required, especially for continuum robots. For this reason, standard approaches for 3-D pose estimation involve the use of external tracking systems. Recently, image-based methods have emerged as promising, non-invasive alternatives. While many image-based approaches in the literature have shown accurate results, they generally require either a complex iterative optimization for each processed image, making them unsuitable for real-time applications, or a large number of manually-annotated images for efficient learning. In this paper we propose a self-supervised image-based method, exploiting, at training time only, the imprecise kinematic information provided by the robot. In order to avoid introducing time-consuming manual annotations, the problem is formulated as an auto-encoder, smartly bottlenecked by the presence of a physical model of the robotic instruments and surgical camera, forcing a separation between image background and kinematic content. Validation of the method was performed on semi-synthetic, phantom and in-vivo datasets, obtained using a flexible robotized endoscope, showing promising results for real-time image-based 3-D pose estimation of surgical instruments.
Distilling Knowledge via Intermediate Classifier Heads
Asadian, Aryan, Salehi-Abari, Amirali
The crux of knowledge distillation -- as a transfer-learning approach -- is to effectively train a resource-limited student model with the guide of a pre-trained larger teacher model. However, when there is a large difference between the model complexities of teacher and student (i.e., capacity gap), knowledge distillation loses its strength in transferring knowledge from the teacher to the student, thus training a weaker student. To mitigate the impact of the capacity gap, we introduce knowledge distillation via intermediate heads. By extending the intermediate layers of the teacher (at various depths) with classifier heads, we cheaply acquire a cohort of heterogeneous pre-trained teachers. The intermediate classifier heads can all together be efficiently learned while freezing the backbone of the pre-trained teacher. The cohort of teachers (including the original teacher) co-teach the student simultaneously. Our experiments on various teacher-student pairs and datasets have demonstrated that the proposed approach outperforms the canonical knowledge distillation approach and its extensions.
Explore User Neighborhood for Real-time E-commerce Recommendation
Xie, Xu, Sun, Fei, Yang, Xiaoyong, Yang, Zhao, Gao, Jinyang, Ou, Wenwu, Cui, Bin
Recommender systems play a vital role in modern online services, such as Amazon and Taobao. Traditional personalized methods, which focus on user-item (UI) relations, have been widely applied in industrial settings, owing to their efficiency and effectiveness. Despite their success, we argue that these approaches ignore local information hidden in similar users. To tackle this problem, user-based methods exploit similar user relations to make recommendations in a local perspective. Nevertheless, traditional user-based methods, like userKNN and matrix factorization, are intractable to be deployed in the real-time applications since such transductive models have to be recomputed or retrained with any new interaction. To overcome this challenge, we propose a framework called self-complementary collaborative filtering~(SCCF) which can make recommendations with both global and local information in real time. On the one hand, it utilizes UI relations and user neighborhood to capture both global and local information. On the other hand, it can identify similar users for each user in real time by inferring user representations on the fly with an inductive model. The proposed framework can be seamlessly incorporated into existing inductive UI approach and benefit from user neighborhood with little additional computation. It is also the first attempt to apply user-based methods in real-time settings. The effectiveness and efficiency of SCCF are demonstrated through extensive offline experiments on four public datasets, as well as a large scale online A/B test in Taobao.
Ultra-Data-Efficient GAN Training: Drawing A Lottery Ticket First, Then Training It Toughly
Chen, Tianlong, Cheng, Yu, Gan, Zhe, Liu, Jingjing, Wang, Zhangyang
Training generative adversarial networks (GANs) with limited data generally results in deteriorated performance and collapsed models. To conquer this challenge, we are inspired by the latest observation of Kalibhat et al. (2020); Chen et al.(2021d), that one can discover independently trainable and highly sparse subnetworks (a.k.a., lottery tickets) from GANs. Treating this as an inductive prior, we decompose the data-hungry GAN training into two sequential sub-problems: (i) identifying the lottery ticket from the original GAN; then (ii) training the found sparse subnetwork with aggressive data and feature augmentations. Both sub-problems re-use the same small training set of real images. Such a coordinated framework enables us to focus on lower-complexity and more data-efficient sub-problems, effectively stabilizing training and improving convergence. Comprehensive experiments endorse the effectiveness of our proposed ultra-data-efficient training framework, across various GAN architectures (SNGAN, BigGAN, and StyleGAN2) and diverse datasets (CIFAR-10, CIFAR-100, Tiny-ImageNet, and ImageNet). Besides, our training framework also displays powerful few-shot generalization ability, i.e., generating high-fidelity images by training from scratch with just 100 real images, without any pre-training. Codes are available at: https://github.com/VITA-Group/Ultra-Data-Efficient-GAN-Training.
Newbie's Deep Learning Tutorial: Learn Keras Machine Learning
Keras is a high-level API, which is aimed to build and train deep learning with Python. This tutorial is created by data scientist and app developer Nimish Narang, which already created more than 20 Mammoth Interactive courses - online tutorials about the web, app, and game development. Python deep learning tutorial is for you if you want to learn the concept of machine learning with practical tasks using Keras, Python, and PyCharm. Any person who understands that technologies shape the way of communication should enroll in this deep learning tutorial for beginners as well. Trust me, after completing this course, new possibilities will open up, as you'll get a new set of skills on new technologies, which are the skills that many employers are looking for. So don't wait up and enroll in this Python machine learning tutorial right away!
Beginning Anomaly Detection Using Python Based Deep Learning PDF
Utilize this easy-to-follow beginner's guide to understand how deep learning can be applied to the task of anomaly detection. Using Keras and PyTorch in Python, the book focuses on how various deep learning models can be applied to semi-supervised and unsupervised anomaly detection tasks. This book begins with an explanation of what anomaly detection is, what it is used for, and its importance. After covering statistical and traditional machine learning methods for anomaly detection using Scikit-Learn in Python, the book then provides an introduction to deep learning with details on how to build and train a deep learning model in both Keras and PyTorch before shifting the focus to applications of the following deep learning models to anomaly detection: various types of Autoencoders, Restricted Boltzmann Machines, RNNs & LSTMs, and Temporal Convolutional Networks. The book explores unsupervised and semi-supervised anomaly detection along with the basics of time series-based anomaly detection.
Artificial Neural Networks (ANN) with Keras in Python and R
Artificial Neural Networks (ANN) with Keras in Python and R, Understand Deep Learning and build Neural Networks using TensorFlow 2.0 and Keras in Python and R Created by Start-Tech AcademyPreview this Course - GET COUPON CODE You're looking for a complete Course on Deep Learning using Keras and Tensorflow that teaches you everything you need to create a Neural Network model in Python and R, right? You've found the right Neural Networks course! After completing this course you will be able to: Identify the business problem which can be solved using Neural network Models. Have a clear understanding of Advanced Neural network concepts such as Gradient Descent, forward and Backward Propagation etc. Create Neural network models in Python and R using Keras and Tensorflow libraries and analyze their results. Confidently practice, discuss and understand Deep Learning concepts How this course will help you?