Deep Learning
Compute and Energy Consumption Trends in Deep Learning Inference
Desislavov, Radosvet, Martínez-Plumed, Fernando, Hernández-Orallo, José
The progress of some AI paradigms such as deep learning is said to be linked to an exponential growth in the number of parameters. There are many studies corroborating these trends, but does this translate into an exponential increase in energy consumption? In order to answer this question we focus on inference costs rather than training costs, as the former account for most of the computing effort, solely because of the multiplicative factors. Also, apart from algorithmic innovations, we account for more specific and powerful hardware (leading to higher FLOPS) that is usually accompanied with important energy efficiency optimisations. We also move the focus from the first implementation of a breakthrough paper towards the consolidated version of the techniques one or two year later. Under this distinctive and comprehensive perspective, we study relevant models in the areas of computer vision and natural language processing: for a sustained increase in performance we see a much softer growth in energy consumption than previously anticipated. The only caveat is, yet again, the multiplicative factor, as future AI increases penetration and becomes more pervasive.
DRo: A data-scarce mechanism to revolutionize the performance of Deep Learning based Security Systems
Sewak, Mohit, Sahay, Sanjay K., Rathore, Hemant
Supervised Deep Learning requires plenty of labeled data to converge, and hence perform optimally for task-specific learning. Therefore, we propose a novel mechanism named DRo (for Deep Routing) for data-scarce domains like security. The DRo approach builds upon some of the recent developments in Deep-Clustering. In particular, it exploits the self-augmented training mechanism using synthetically generated local perturbations. DRo not only allays the challenges with sparse-labeled data but also offers many unique advantages. We also developed a system named DRoID that uses the DRo mechanism for enhancing the performance of an existing Malware Detection System that uses (low information features like the) Android implicit Intent(s) as the only features. We conduct experiments on DRoID using a popular and standardized Android malware dataset and found that the DRo mechanism could successfully reduce the false-alarms generated by the downstream classifier by 67.9%, and also simultaneously boosts its accuracy by 11.3%. This is significant not only because the gains achieved are unparalleled but also because the features used were never considered rich enough to train a classifier on; and hence no decent performance could ever be reported by any malware classification system till-date using these features in isolation. Owing to the results achieved, the DRo mechanism claims a dominant position amongst all known systems that aims to enhance the classification performance of deep learning models with sparse-labeled data.
The Logic Traps in Evaluating Post-hoc Interpretations
Ju, Yiming, Zhang, Yuanzhe, Yang, Zhao, Jiang, Zhongtao, Liu, Kang, Zhao, Jun
The lack of a clear statement on these traps has damaged the The inscrutability of deep models has grown in tandem community in the following aspects: with their power (Doshi-Velez and Kim, 2017), which has motivated efforts to interpret how these First, different evaluation methods may give rise black-box models work (Sundararajan et al., 2017; to contradictory conclusions, which has caused Belinkov and Glass, 2019). Post-hoc interpretation many debates, such as the argument in using the aims to explain a trained model and reveal how magnitudes of attention weights as interpretations the model arrives at a decision. This interpretability for transformer-based models (Wiegreffe and Pinter, is achieved by interpreting a trained model in 2019; Jain and Wallace, 2019; Pruthi et al., post-hoc ways (Molnar, 2020).
Not All Negatives are Equal: Label-Aware Contrastive Loss for Fine-grained Text Classification
Suresh, Varsha, Ong, Desmond C.
Fine-grained classification involves dealing with datasets with larger number of classes with subtle differences between them. Guiding the model to focus on differentiating dimensions between these commonly confusable classes is key to improving performance on fine-grained tasks. In this work, we analyse the contrastive fine-tuning of pre-trained language models on two fine-grained text classification tasks, emotion classification and sentiment analysis. We adaptively embed class relationships into a contrastive objective function to help differently weigh the positives and negatives, and in particular, weighting closely confusable negatives more than less similar negative examples. We find that Label-aware Contrastive Loss outperforms previous contrastive methods, in the presence of larger number and/or more confusable classes, and helps models to produce output distributions that are more differentiated.
Inferential Wasserstein Generative Adversarial Networks
Chen, Yao, Gao, Qingyi, Wang, Xiao
Generative Adversarial Networks (GANs) have been impactful on many problems and applications but suffer from unstable training. The Wasserstein GAN (WGAN) leverages the Wasserstein distance to avoid the caveats in the minmax two-player training of GANs but has other defects such as mode collapse and lack of metric to detect the convergence. We introduce a novel inferential Wasserstein GAN (iWGAN) model, which is a principled framework to fuse auto-encoders and WGANs. The iWGAN model jointly learns an encoder network and a generator network motivated by the iterative primal dual optimization process. The encoder network maps the observed samples to the latent space and the generator network maps the samples from the latent space to the data space. We establish the generalization error bound of the iWGAN to theoretically justify its performance. We further provide a rigorous probabilistic interpretation of our model under the framework of maximum likelihood estimation. The iWGAN, with a clear stopping criteria, has many advantages over other autoencoder GANs. The empirical experiments show that the iWGAN greatly mitigates the symptom of mode collapse, speeds up the convergence, and is able to provide a measurement of quality check for each individual sample. We illustrate the ability of the iWGAN by obtaining competitive and stable performances for benchmark datasets.
Critical Learning Periods in Federated Learning
Yan, Gang, Wang, Hao, Li, Jian
Federated learning (FL) is a popular technique to train machine learning (ML) models with decentralized data. Extensive works have studied the performance of the global model; however, it is still unclear how the training process affects the final test accuracy. Exacerbating this problem is the fact that FL executions differ significantly from traditional ML with heterogeneous data characteristics across clients, involving more hyperparameters. In this work, we show that the final test accuracy of FL is dramatically affected by the early phase of the training process, i.e., FL exhibits critical learning periods, in which small gradient errors can have irrecoverable impact on the final test accuracy. To further explain this phenomenon, we generalize the trace of the Fisher Information Matrix (FIM) to FL and define a new notion called FedFIM, a quantity reflecting the local curvature of each clients from the beginning of the training in FL. Our findings suggest that the {\em initial learning phase} plays a critical role in understanding the FL performance. This is in contrast to many existing works which generally do not connect the final accuracy of FL to the early phase training. Finally, seizing critical learning periods in FL is of independent interest and could be useful for other problems such as the choices of hyperparameters such as the number of client selected per round, batch size, and more, so as to improve the performance of FL training and testing.
Computer vision and deep learning provide new ways to detect cyber threats
This article is part of our reviews of AI research papers, a series of posts that explore the latest findings in artificial intelligence. The last decade's growing interest in deep learning was triggered by the proven capacity of neural networks in computer vision tasks. If you train a neural network with enough labeled photos of cats and dogs, it will be able to find recurring patterns in each category and classify unseen images with decent accuracy. What else can you do with an image classifier? In 2019, a group of cybersecurity researchers wondered if they could treat security threat detection as an image classification problem.
Cognitive Analytics Answers the Question: What's Interesting in Your Data?
Dimensionality reduction is a critical component of any solution dealing with massive data collections. Being able to sift through a mountain of data efficiently in order to find the key descriptive, predictive and explanatory features of the collection is a fundamental required capability for coping with the avalanche of data that all organizations are collecting. Identifying the most interesting dimensions of data is especially critical when integrating high-dimensional (high-variety) complex data sources, then attempting to visualize the most insightful patterns in the data, and then telling the data's story to your stakeholders. There is a "good news, bad news" angle here. First, the bad news: the human capacity for visualizing multiple dimensions is very limited: 3 or 4 dimensions are manageable; 5 or 6 dimensions are possible (e.g., with colors and symbols); but more dimensions are difficult-to-impossible to assimilate.
Training and Testing Neural Networks on PyTorch using Ignite
With ignite, you can write loops to train the network in just a few lines, add standard metrics calculation out of the box, save the model, etc. Well, for those who have moved from TF to PyTorch, we can say that the ignite – Keras library for PyTorch. I will not spend time talking about how cool the framework PyTorch is. Anyone who has already used it understands what I am writing about. But, with all its advantages, it is still low-level in terms of writing loops for training, checking, testing neural networks.
NVIDIA Research: Tensors Are the Future of Deep Learning
This post discusses tensor methods, how they are used in NVIDIA, and how they are central to the next generation of AI algorithms. Tensors, which generalize matrices to more than two dimensions, are everywhere in modern machine learning. From deep neural networks features to videos or fMRI data, the structure in these higher-order tensors is often crucial. Deep neural networks typically map between higher-order tensors. In fact, it is the ability of deep convolutional neural networks to preserve and leverage local structure that made the current levels of performance possible, along with large datasets and efficient hardware. Tensor methods enable you to preserve and leverage that structure further, for individual layers or whole networks.