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 Deep Learning


Nonlinear Acceleration of CNNs

arXiv.org Machine Learning

The Regularized Nonlinear Acceleration (RNA) algorithm is an acceleration method capable of improving the rate of convergence of many optimization schemes such as gradient descend, SAGA or SVRG. Until now, its analysis is limited to convex problems, but empirical observations shows that RNA may be extended to wider settings. In this paper, we investigate further the benefits of RNA when applied to neural networks, in particular for the task of image recognition on CIFAR10 and ImageNet. With very few modifications of exiting frameworks, RNA improves slightly the optimization process of CNNs, after training.


Learning Neural Random Fields with Inclusive Auxiliary Generators

arXiv.org Machine Learning

In this paper we develop Neural Random Field learning with Inclusive-divergence minimized Auxiliary Generators (NRF-IAG), which is under-appreciated in the literature. The contributions are two-fold. First, we rigorously apply the stochastic approximation algorithm to solve the joint optimization and provide theoretical justification. The new approach of learning NRF-IAG achieves superior unsupervised learning performance competitive with state-of-the-art deep generative models (DGMs) in terms of sample generation quality. Second, semi-supervised learning (SSL) with NRF-IAG gives rise to strong classification results comparable to state-of-art DGM-based SSL methods, and simultaneously achieves superior generation. This is in contrast to the conflict of good classification and good generation, as observed in GAN-based SSL.


Learn the new, keep the old: Extending pretrained models with new anatomy and images

arXiv.org Machine Learning

Deep learning has been widely accepted as a promising solution for medical image segmentation, given a sufficiently large representative dataset of images with corresponding annotations. With ever increasing amounts of annotated medical datasets, it is infeasible to train a learning method always with all data from scratch. This is also doomed to hit computational limits, e.g., memory or runtime feasible for training. Incremental learning can be a potential solution, where new information (images or anatomy) is introduced iteratively. Nevertheless, for the preservation of the collective information, it is essential to keep some "important" (i.e., representative) images and annotations from the past, while adding new information. In this paper, we introduce a framework for applying incremental learning for segmentation and propose novel methods for selecting representative data therein. We comparatively evaluate our methods in different scenarios using MR images and validate the increased learning capacity with using our methods.


TAPAS: Train-less Accuracy Predictor for Architecture Search

arXiv.org Machine Learning

In recent years an increasing number of researchers and practitioners have been suggesting algorithms for large-scale neural network architecture search: genetic algorithms, reinforcement learning, learning curve extrapolation, and accuracy predictors. None of them, however, demonstrated high-performance without training new experiments in the presence of unseen datasets. We propose a new deep neural network accuracy predictor, that estimates in fractions of a second classification performance for unseen input datasets, without training. In contrast to previously proposed approaches, our prediction is not only calibrated on the topological network information, but also on the characterization of the dataset-difficulty which allows us to re-tune the prediction without any training. Our predictor achieves a performance which exceeds 100 networks per second on a single GPU, thus creating the opportunity to perform large-scale architecture search within a few minutes. We present results of two searches performed in 400 seconds on a single GPU. Our best discovered networks reach 93.67% accuracy for CIFAR-10 and 81.01% for CIFAR-100, verified by training. These networks are performance competitive with other automatically discovered state-of-the-art networks however we only needed a small fraction of the time to solution and computational resources.


Being curious about the answers to questions: novelty search with learned attention

arXiv.org Machine Learning

We investigate the use of attentional neural network layers in order to learn a `behavior characterization' which can be used to drive novelty search and curiosity-based policies. The space is structured towards answering a particular distribution of questions, which are used in a supervised way to train the attentional neural network. We find that in a 2d exploration task, the structure of the space successfully encodes local sensory-motor contingencies such that even a greedy local `do the most novel action' policy with no reinforcement learning or evolution can explore the space quickly. We also apply this to a high/low number guessing game task, and find that guessing according to the learned attention profile performs active inference and can discover the correct number more quickly than an exact but passive approach.


Learning a Latent Space of Multitrack Measures

arXiv.org Machine Learning

Some of these models learn a latent space: a lowerdimensional representation that can be mapped to and from the object space. A major advantage of such latent space models is that many operations that would be difficult to perform in the object space, like morphing between two objects in a semantically meaningful way, become straightforward arithmetic in the latent space. It has even been claimed that latent space models can augment human understanding of the object domain [6]. Latent space models have already been trained for several musical concepts including raw waveforms of notes [12], melodies and drum tracks [33], and playlists [38]. Such models are also frequently used for music recommendations [23], where both user "taste" and song "style" are reasoned about in terms of latent vectors. In this paper, we present a latent space model of individual measures of music with multi-instrument polyphony and dynamics. One way to think about such objects is as musical textures; however, we do not model the audio itself but rather use a symbolic representation of the music. This latent space model allows us to perform a number of intuitive operations: - Sample a measure from the prior distribution to generate novel music from scratch.


Implicit Reparameterization Gradients

arXiv.org Machine Learning

By providing a simple and efficient way of computing low-variance gradients of continuous random variables, the reparameterization trick has become the technique of choice for training a variety of latent variable models. However, it is not applicable to a number of important continuous distributions. We introduce an alternative approach to computing reparameterization gradients based on implicit differentiation and demonstrate its broader applicability by applying it to Gamma, Beta, Dirichlet, and von Mises distributions, which cannot be used with the classic reparameterization trick. Our experiments show that the proposed approach is faster and more accurate than the existing gradient estimators for these distributions.


NetGAN: Generating Graphs via Random Walks

arXiv.org Machine Learning

We propose NetGAN - the first implicit generative model for graphs able to mimic real-world networks. We pose the problem of graph generation as learning the distribution of biased random walks over the input graph. The proposed model is based on a stochastic neural network that generates discrete output samples and is trained using the Wasserstein GAN objective. NetGAN is able to produce graphs that exhibit well-known network patterns without explicitly specifying them in the model definition. At the same time, our model exhibits strong generalization properties, as highlighted by its competitive link prediction performance, despite not being trained specifically for this task. Being the first approach to combine both of these desirable properties, Net-GAN opens exciting avenues for further research.


Text Mining and Sentiment Analysis - A Primer

@machinelearnbot

Over years, a crucial part of data-gathering behavior has revolved around what other people think. With the constantly growing popularity and availability of opinion-driven resources such as personal blogs and online review sites, new challenges and opportunities are emerging as people have started using advanced technologies to make decisions now. Sentiment analysis or opinion mining, refers to the use of computational linguistics, text analytics and natural language processing to identify and extract information from source materials. Sentiment analysis is considered one of the most popular applications of text analytics. The primary aspect of sentiment analysis includes data analysis on the body of the text for understanding the opinion expressed by it and other key factors comprising modality and mood.


Weights & Biases

#artificialintelligence

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