January 28, 2020

2957 words 14 mins read

Paper Group ANR 994

Paper Group ANR 994

Order Matters at Fanatics Recommending Sequentially Ordered Products by LSTM Embedded with Word2Vec. Using multi-task learning to improve the performance of acoustic-to-word and conventional hybrid models. A stochastic alternating minimizing method for sparse phase retrieval. Convex Reconstruction of Structured Matrix Signals from Linear Measuremen …

Order Matters at Fanatics Recommending Sequentially Ordered Products by LSTM Embedded with Word2Vec

Title Order Matters at Fanatics Recommending Sequentially Ordered Products by LSTM Embedded with Word2Vec
Authors Jing Pan, Weian Sheng, Santanu Dey
Abstract A unique challenge for e-commerce recommendation is that customers are often interested in products that are more advanced than their already purchased products, but not reversed. The few existing recommender systems modeling unidirectional sequence output a limited number of categories or continuous variables. To model the ordered sequence, we design the first recommendation system that both embed purchased items with Word2Vec, and model the sequence with stateless LSTM RNN. The click-through rate of this recommender system in production outperforms its solely Word2Vec based predecessor. Developed in 2017, it was perhaps the first published real-world application that makes distributed predictions of a single machine trained Keras model on Spark slave nodes at a scale of more than 0.4 million columns per row.
Tasks Recommendation Systems
Published 2019-11-22
URL https://arxiv.org/abs/1911.09818v1
PDF https://arxiv.org/pdf/1911.09818v1.pdf
PWC https://paperswithcode.com/paper/order-matters-at-fanatics-recommending
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Using multi-task learning to improve the performance of acoustic-to-word and conventional hybrid models

Title Using multi-task learning to improve the performance of acoustic-to-word and conventional hybrid models
Authors Thai-Son Nguyen, Sebastian Stueker, Alex Waibel
Abstract Acoustic-to-word (A2W) models that allow direct mapping from acoustic signals to word sequences are an appealing approach to end-to-end automatic speech recognition due to their simplicity. However, prior works have shown that modelling A2W typically encounters issues of data sparsity that prevent training such a model directly. So far, pre-training initialization is the only approach proposed to deal with this issue. In this work, we propose to build a shared neural network and optimize A2W and conventional hybrid models in a multi-task manner. Our results show that training an A2W model is much more stable with our multi-task model without pre-training initialization, and results in a significant improvement compared to a baseline model. Experiments also reveal that the performance of a hybrid acoustic model can be further improved when jointly training with a sequence-level optimization criterion such as acoustic-to-word.
Tasks Multi-Task Learning, Speech Recognition
Published 2019-02-02
URL https://arxiv.org/abs/1902.01951v2
PDF https://arxiv.org/pdf/1902.01951v2.pdf
PWC https://paperswithcode.com/paper/using-multi-task-learning-to-improve-the
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A stochastic alternating minimizing method for sparse phase retrieval

Title A stochastic alternating minimizing method for sparse phase retrieval
Authors Jianfeng Cai, Yuling Jiao, Xiliang Lu, Juntao You
Abstract Sparse phase retrieval plays an important role in many fields of applied science and thus attracts lots of attention. In this paper, we propose a \underline{sto}chastic alte\underline{r}nating \underline{m}inimizing method for \underline{sp}arse ph\underline{a}se \underline{r}etrieval (\textit{StormSpar}) algorithm which {emprically} is able to recover $n$-dimensional $s$-sparse signals from only $O(s,\mathrm{log}, n)$ number of measurements without a desired initial value required by many existing methods. In \textit{StormSpar}, the hard-thresholding pursuit (HTP) algorithm is employed to solve the sparse constraint least square sub-problems. The main competitive feature of \textit{StormSpar} is that it converges globally requiring optimal order of number of samples with random initialization. Extensive numerical experiments are given to validate the proposed algorithm.
Tasks
Published 2019-06-14
URL https://arxiv.org/abs/1906.05967v1
PDF https://arxiv.org/pdf/1906.05967v1.pdf
PWC https://paperswithcode.com/paper/a-stochastic-alternating-minimizing-method
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Convex Reconstruction of Structured Matrix Signals from Linear Measurements (I): Theoretical Results

Title Convex Reconstruction of Structured Matrix Signals from Linear Measurements (I): Theoretical Results
Authors Yuan Tian
Abstract We investigate the problem of reconstructing n-by-n structured matrix signal X via convex programming, where each column xj is a vector of s-sparsity and all columns have the same l1-norm. The regularizer in use is matrix norm X1=maxjxj1.The contribution in this paper has two parts. The first part is about conditions for stability and robustness in signal reconstruction via solving the convex programming from noise-free or noisy measurements.We establish uniform sufficient conditions which are very close to necessary conditions and non-uniform conditions are also discussed. Similar as the traditional compressive sensing theory for reconstructing vector signals, a related RIP condition is established. In addition, stronger conditions are investigated to guarantee the reconstructed signal’s support stability, sign stability and approximation-error robustness. The second part is to establish upper and lower bounds on number of measurements for robust reconstruction in noise. We take the convex geometric approach in random measurement setting and one of the critical ingredients in this approach is to estimate the related widths bounds in case of Gaussian and non-Gaussian distributions. These bounds are explicitly controlled by signal’s structural parameters r and s which determine matrix signal’s column-wise sparsity and l1-column-flatness respectively.
Tasks Compressive Sensing
Published 2019-10-19
URL https://arxiv.org/abs/1910.08771v4
PDF https://arxiv.org/pdf/1910.08771v4.pdf
PWC https://paperswithcode.com/paper/convex-reconstruction-of-structured-matrix
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Sparse Polynomial Chaos expansions using Variational Relevance Vector Machines

Title Sparse Polynomial Chaos expansions using Variational Relevance Vector Machines
Authors Panagiotis Tsilifis, Iason Papaioannou, Daniel Straub, Fabio Nobile
Abstract The challenges for non-intrusive methods for Polynomial Chaos modeling lie in the computational efficiency and accuracy under a limited number of model simulations. These challenges can be addressed by enforcing sparsity in the series representation through retaining only the most important basis terms. In this work, we present a novel sparse Bayesian learning technique for obtaining sparse Polynomial Chaos expansions which is based on a Relevance Vector Machine model and is trained using Variational Inference. The methodology shows great potential in high-dimensional data-driven settings using relatively few data points and achieves user-controlled sparse levels that are comparable to other methods such as compressive sensing. The proposed approach is illustrated on two numerical examples, a synthetic response function that is explored for validation purposes and a low-carbon steel plate with random Young’s modulus and random loading, which is modeled by stochastic finite element with 38 input random variables.
Tasks Compressive Sensing
Published 2019-12-23
URL https://arxiv.org/abs/1912.11029v1
PDF https://arxiv.org/pdf/1912.11029v1.pdf
PWC https://paperswithcode.com/paper/sparse-polynomial-chaos-expansions-using
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Regularizing Neural Networks via Stochastic Branch Layers

Title Regularizing Neural Networks via Stochastic Branch Layers
Authors Wonpyo Park, Paul Hongsuck Seo, Bohyung Han, Minsu Cho
Abstract We introduce a novel stochastic regularization technique for deep neural networks, which decomposes a layer into multiple branches with different parameters and merges stochastically sampled combinations of the outputs from the branches during training. Since the factorized branches can collapse into a single branch through a linear operation, inference requires no additional complexity compared to the ordinary layers. The proposed regularization method, referred to as StochasticBranch, is applicable to any linear layers such as fully-connected or convolution layers. The proposed regularizer allows the model to explore diverse regions of the model parameter space via multiple combinations of branches to find better local minima. An extensive set of experiments shows that our method effectively regularizes networks and further improves the generalization performance when used together with other existing regularization techniques.
Tasks
Published 2019-10-03
URL https://arxiv.org/abs/1910.01467v1
PDF https://arxiv.org/pdf/1910.01467v1.pdf
PWC https://paperswithcode.com/paper/regularizing-neural-networks-via-stochastic
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Robust Compressive Sensing MRI Reconstruction using Generative Adversarial Networks

Title Robust Compressive Sensing MRI Reconstruction using Generative Adversarial Networks
Authors Puneesh Deora, Bhavya Vasudeva, Saumik Bhattacharya, Pyari Mohan Pradhan
Abstract Compressive sensing magnetic resonance imaging (CS-MRI) accelerates the acquisition of MR images by breaking the Nyquist sampling limit. In this work, a novel generative adversarial network (GAN) based framework for CS-MRI reconstruction is proposed. Leveraging a combination of patchGAN discriminator and structural similarity index based loss, our model focuses on preserving high frequency content as well as fine textural details in the reconstructed image. Dense and residual connections have been incorporated in a U-net based generator architecture to allow easier transfer of information as well as variable network length. We show that our algorithm outperforms state-of-the-art methods in terms of quality of reconstruction and robustness to noise. Also, the reconstruction time, which is of the order of milliseconds, makes it highly suitable for real-time clinical use.
Tasks Compressive Sensing
Published 2019-10-14
URL https://arxiv.org/abs/1910.06067v1
PDF https://arxiv.org/pdf/1910.06067v1.pdf
PWC https://paperswithcode.com/paper/robust-compressive-sensing-mri-reconstruction
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What Happens on the Edge, Stays on the Edge: Toward Compressive Deep Learning

Title What Happens on the Edge, Stays on the Edge: Toward Compressive Deep Learning
Authors Yang Li, Thomas Strohmer
Abstract Machine learning at the edge offers great benefits such as increased privacy and security, low latency, and more autonomy. However, a major challenge is that many devices, in particular edge devices, have very limited memory, weak processors, and scarce energy supply. We propose a hybrid hardware-software framework that has the potential to significantly reduce the computational complexity and memory requirements of on-device machine learning. In the first step, inspired by compressive sensing, data is collected in compressed form simultaneously with the sensing process. Thus this compression happens already at the hardware level during data acquisition. But unlike in compressive sensing, this compression is achieved via a projection operator that is specifically tailored to the desired machine learning task. The second step consists of a specially designed and trained deep network. As concrete example we consider the task of image classification, although the proposed framework is more widely applicable. An additional benefit of our approach is that it can be easily combined with existing on-device techniques. Numerical simulations illustrate the viability of our method.
Tasks Compressive Sensing, Image Classification
Published 2019-09-04
URL https://arxiv.org/abs/1909.01539v1
PDF https://arxiv.org/pdf/1909.01539v1.pdf
PWC https://paperswithcode.com/paper/what-happens-on-the-edge-stays-on-the-edge
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Information-Theoretic Lower Bounds for Compressive Sensing with Generative Models

Title Information-Theoretic Lower Bounds for Compressive Sensing with Generative Models
Authors Zhaoqiang Liu, Jonathan Scarlett
Abstract It has recently been shown that for compressive sensing, significantly fewer measurements may be required if the sparsity assumption is replaced by the assumption the unknown vector lies near the range of a suitably-chosen generative model. In particular, in (Bora {\em et al.}, 2017) it was shown roughly $O(k\log L)$ random Gaussian measurements suffice for accurate recovery when the generative model is an $L$-Lipschitz function with bounded $k$-dimensional inputs, and $O(kd \log w)$ measurements suffice when the generative model is a $k$-input ReLU network with depth $d$ and width $w$. In this paper, we establish corresponding algorithm-independent lower bounds on the sample complexity using tools from minimax statistical analysis. In accordance with the above upper bounds, our results are summarized as follows: (i) We construct an $L$-Lipschitz generative model capable of generating group-sparse signals, and show that the resulting necessary number of measurements is $\Omega(k \log L)$; (ii) Using similar ideas, we construct ReLU networks with high depth and/or high depth for which the necessary number of measurements scales as $\Omega\big( kd \frac{\log w}{\log n}\big)$ (with output dimension $n$), and in some cases $\Omega(kd \log w)$. As a result, we establish that the scaling laws derived in (Bora {\em et al.}, 2017) are optimal or near-optimal in the absence of further assumptions.
Tasks Compressive Sensing
Published 2019-08-28
URL https://arxiv.org/abs/1908.10744v2
PDF https://arxiv.org/pdf/1908.10744v2.pdf
PWC https://paperswithcode.com/paper/information-theoretic-lower-bounds-for-2
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Multi-Channel Deep Networks for Block-Based Image Compressive Sensing

Title Multi-Channel Deep Networks for Block-Based Image Compressive Sensing
Authors Siwang Zhou, Yan He, Yonghe Liu, Chengqing Li
Abstract Incorporating deep neural networks in image compressive sensing (CS) receives intensive attentions recently. As deep network approaches learn the inverse mapping directly from the CS measurements, a number of models have to be trained, each of which corresponds to a sampling rate. This may potentially degrade the performance of image CS, especially when multiple sampling rates are assigned to different blocks within an image. In this paper, we develop a multi-channel deep network for block-based image CS with performance significantly exceeding the current state-of-the-art methods. The significant performance improvement of the model is attributed to block-based sampling rates allocation and model-level removal of blocking artifacts. Specifically, the image blocks with a variety of sampling rates can be reconstructed in a single model by exploiting inter-block correlation. At the same time, the initially reconstructed blocks are reassembled into a full image to remove blocking artifacts within the network by unrolling a hand-designed block-based CS algorithm. Experimental results demonstrate that the proposed method outperforms the state-of-the-art CS methods by a large margin in terms of objective metrics, PSNR, SSIM, and subjective visual quality.
Tasks Compressive Sensing
Published 2019-08-28
URL https://arxiv.org/abs/1908.11221v1
PDF https://arxiv.org/pdf/1908.11221v1.pdf
PWC https://paperswithcode.com/paper/multi-channel-deep-networks-for-block-based
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Few-Shot Dialogue Generation Without Annotated Data: A Transfer Learning Approach

Title Few-Shot Dialogue Generation Without Annotated Data: A Transfer Learning Approach
Authors Igor Shalyminov, Sungjin Lee, Arash Eshghi, Oliver Lemon
Abstract Learning with minimal data is one of the key challenges in the development of practical, production-ready goal-oriented dialogue systems. In a real-world enterprise setting where dialogue systems are developed rapidly and are expected to work robustly for an ever-growing variety of domains, products, and scenarios, efficient learning from a limited number of examples becomes indispensable. In this paper, we introduce a technique to achieve state-of-the-art dialogue generation performance in a few-shot setup, without using any annotated data. We do this by leveraging background knowledge from a larger, more highly represented dialogue source — namely, the MetaLWOz dataset. We evaluate our model on the Stanford Multi-Domain Dialogue Dataset, consisting of human-human goal-oriented dialogues in in-car navigation, appointment scheduling, and weather information domains. We show that our few-shot approach achieves state-of-the art results on that dataset by consistently outperforming the previous best model in terms of BLEU and Entity F1 scores, while being more data-efficient by not requiring any data annotation.
Tasks Dialogue Generation, Goal-Oriented Dialogue Systems, Transfer Learning
Published 2019-08-16
URL https://arxiv.org/abs/1908.05854v1
PDF https://arxiv.org/pdf/1908.05854v1.pdf
PWC https://paperswithcode.com/paper/few-shot-dialogue-generation-without
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ISEA: Image Steganalysis using Evolutionary Algorithms

Title ISEA: Image Steganalysis using Evolutionary Algorithms
Authors Farid Ghareh Mohammadi, Hamid R. Arabnia
Abstract NP-hard problems always have been attracting scientists’ attentions, and most often seen in the emerging challenging issues. The most interesting NP-hard problems emerging in the world of data science is Curse of dimensionality (CoD). Recently, this problem has penetrated most of high technology domains like advanced image processing, particularly image steganalysis. The universal and smarter steganalysis algorithms provide a huge number of attributes, which make working with data hard to process. In large data sets, finding a pattern which governs whole data takes long time, and yet no guarantee to reach the optimal pattern. In general, the purpose of the researchers in image steganalysis stands for distinguishing stego images from cover images. In this paper, we investigated recent works on detecting stego images, particularly those algorithms that adopted evolutionary algorithms. Thus, our work is categorized as supervised learning which consider ground truth to evaluate the performance of given algorithm. The objective is to provide a comprehensive understanding of evolutionary algorithms which are attempted to solve this NP-hard problems.
Tasks
Published 2019-07-23
URL https://arxiv.org/abs/1907.12914v1
PDF https://arxiv.org/pdf/1907.12914v1.pdf
PWC https://paperswithcode.com/paper/isea-image-steganalysis-using-evolutionary
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Learning Ontologies with Epistemic Reasoning: The EL Case

Title Learning Ontologies with Epistemic Reasoning: The EL Case
Authors Ana Ozaki, Nicolas Troquard
Abstract We investigate the problem of learning description logic ontologies from entailments via queries, using epistemic reasoning. We introduce a new learning model consisting of epistemic membership and example queries and show that polynomial learnability in this model coincides with polynomial learnability in Angluin’s exact learning model with membership and equivalence queries. We then instantiate our learning framework to EL and show some complexity results for an epistemic extension of EL where epistemic operators can be applied over the axioms. Finally, we transfer known results for EL ontologies and its fragments to our learning model based on epistemic reasoning.
Tasks
Published 2019-02-08
URL http://arxiv.org/abs/1902.03273v1
PDF http://arxiv.org/pdf/1902.03273v1.pdf
PWC https://paperswithcode.com/paper/learning-ontologies-with-epistemic-reasoning
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Seek and You Will Find: A New Optimized Framework for Efficient Detection of Pedestrian

Title Seek and You Will Find: A New Optimized Framework for Efficient Detection of Pedestrian
Authors Sudip Das, Partha Sarathi Mukherjee, Ujjwal Bhattacharya
Abstract Studies of object detection and localization, particularly pedestrian detection have received considerable attention in recent times due to its several prospective applications such as surveillance, driving assistance, autonomous cars, etc. Also, a significant trend of latest research studies in related problem areas is the use of sophisticated Deep Learning based approaches to improve the benchmark performance on various standard datasets. A trade-off between the speed (number of video frames processed per second) and detection accuracy has often been reported in the existing literature. In this article, we present a new but simple deep learning based strategy for pedestrian detection that improves this trade-off. Since training of similar models using publicly available sample datasets failed to improve the detection performance to some significant extent, particularly for the instances of pedestrians of smaller sizes, we have developed a new sample dataset consisting of more than 80K annotated pedestrian figures in videos recorded under varying traffic conditions. Performance of the proposed model on the test samples of the new dataset and two other existing datasets, namely Caltech Pedestrian Dataset (CPD) and CityPerson Dataset (CD) have been obtained. Our proposed system shows nearly 16% improvement over the existing state-of-the-art result.
Tasks Object Detection, Pedestrian Detection
Published 2019-12-21
URL https://arxiv.org/abs/1912.10241v1
PDF https://arxiv.org/pdf/1912.10241v1.pdf
PWC https://paperswithcode.com/paper/seek-and-you-will-find-a-new-optimized
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Geometry and Symmetry in Short-and-Sparse Deconvolution

Title Geometry and Symmetry in Short-and-Sparse Deconvolution
Authors Han-Wen Kuo, Yenson Lau, Yuqian Zhang, John Wright
Abstract We study the $\textit{Short-and-Sparse (SaS) deconvolution}$ problem of recovering a short signal $\mathbf a_0$ and a sparse signal $\mathbf x_0$ from their convolution. We propose a method based on nonconvex optimization, which under certain conditions recovers the target short and sparse signals, up to a signed shift symmetry which is intrinsic to this model. This symmetry plays a central role in shaping the optimization landscape for deconvolution. We give a $\textit{regional analysis}$, which characterizes this landscape geometrically, on a union of subspaces. Our geometric characterization holds when the length-$p_0$ short signal $\mathbf a_0$ has shift coherence $\mu$, and $\mathbf x_0$ follows a random sparsity model with sparsity rate $\theta \in \Bigl[\frac{c_1}{p_0}, \frac{c_2}{p_0\sqrt\mu + \sqrt{p_0}}\Bigr]\cdot\frac{1}{\log^2p_0}$. Based on this geometry, we give a provable method that successfully solves SaS deconvolution with high probability.
Tasks
Published 2019-01-02
URL http://arxiv.org/abs/1901.00256v2
PDF http://arxiv.org/pdf/1901.00256v2.pdf
PWC https://paperswithcode.com/paper/geometry-and-symmetry-in-short-and-sparse
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