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Exploiting Nontrivial Connectivity for Automatic Speech Recognition

arXiv.org Machine Learning

Nontrivial connectivity has allowed the training of very deep networks by addressing the problem of vanishing gradients and offering a more efficient method of reusing parameters. In this paper we make a comparison between residual networks, densely-connected networks and highway networks on an image classification task. Next, we show that these methodologies can easily be deployed into automatic speech recognition and provide significant improvements to existing models.


Learning to Rank based on Analogical Reasoning

arXiv.org Machine Learning

Object ranking or "learning to rank" is an important problem in the realm of preference learning. On the basis of training data in the form of a set of rankings of objects represented as feature vectors, the goal is to learn a ranking function that predicts a linear order of any new set of objects. In this paper, we propose a new approach to object ranking based on principles of analogical reasoning. More specifically, our inference pattern is formalized in terms of so-called analogical proportions and can be summarized as follows: Given objects $A,B,C,D$, if object $A$ is known to be preferred to $B$, and $C$ relates to $D$ as $A$ relates to $B$, then $C$ is (supposedly) preferred to $D$. Our method applies this pattern as a main building block and combines it with ideas and techniques from instance-based learning and rank aggregation. Based on first experimental results for data sets from various domains (sports, education, tourism, etc.), we conclude that our approach is highly competitive. It appears to be specifically interesting in situations in which the objects are coming from different subdomains, and which hence require a kind of knowledge transfer.


Quantitative CBA: Small and Comprehensible Association Rule Classification Models

arXiv.org Machine Learning

Quantitative CBA is a postprocessing algorithm for association rule classification algorithm CBA (Liu et al, 1998). QCBA uses original, undiscretized numerical attributes to optimize the discovered association rules, refining the boundaries of literals in the antecedent of the rules produced by CBA. Some rules as well as literals from the rules can consequently be removed, which makes the resulting classifier smaller. One-rule classification and crisp rules make CBA classification models possibly most comprehensible among all association rule classification algorithms. These viable properties are retained by QCBA. The postprocessing is conceptually fast, because it is performed on a relatively small number of rules that passed data coverage pruning in CBA. Benchmark of our QCBA approach on 22 UCI datasets shows average 53% decrease in the total size of the model as measured by the total number of conditions in all rules. Model accuracy remains on the same level as for CBA.


Structured Probabilistic Pruning for Convolutional Neural Network Acceleration

arXiv.org Machine Learning

Although deep Convolutional Neural Network (CNN) has shown better performance in various computer vision tasks, its application is restricted by a significant increase in storage and computation. Among CNN simplification techniques, parameter pruning is a promising approach which aims at reducing the number of weights of various layers without intensively reducing the original accuracy. In this paper, we propose a novel progressive parameter pruning method, named Structured Probabilistic Pruning (SPP), which effectively prunes weights of convolutional layers in a probabilistic manner. Specifically, unlike existing deterministic pruning approaches, where unimportant weights are permanently eliminated, SPP introduces a pruning probability for each weight, and pruning is guided by sampling from the pruning probabilities. A mechanism is designed to increase and decrease pruning probabilities based on importance criteria for the training process. Experiments show that, with 4x speedup, SPP can accelerate AlexNet with only 0.3% loss of top-5 accuracy and VGG-16 with 0.8% loss of top-5 accuracy in ImageNet classification. Moreover, SPP can be directly applied to accelerate multi-branch CNN networks, such as ResNet, without specific adaptations. Our 2x speedup ResNet-50 only suffers 0.8% loss of top-5 accuracy on ImageNet. We further prove the effectiveness of our method on transfer learning task on Flower-102 dataset with AlexNet.


On the Opportunities and Pitfalls of Nesting Monte Carlo Estimators

arXiv.org Machine Learning

We present a formalization of nested Monte Carlo (NMC) estimation, whereby terms in an outer estimator themselves involve calculation of separate, nested, Monte Carlo (MC) estimators. We demonstrate that, under mild conditions, NMC can provide consistent estimates of nested expectations, including cases involving arbitrary levels of nesting; establish corresponding rates of convergence; and provide empirical evidence that these rates are observed in practice. We further establish a number of pitfalls that can arise from naïve nesting of MC estimators, provide guidelines about how these can be avoided, and lay out novel methods for reformulating certain classes of nested expectation problems into single expectations, leading to improved convergence rates. Finally, we use one of these reformulations to derive a new estimator for use in discrete Bayesian experimental design problems which has a better convergence rate than existing methods. Our results have implications for a wide range of fields from probabilistic programming to deep generative models and serve both as an invitation for further inquiry and a caveat against careless use.


Stochastic approximation for speeding up LSTD (and LSPI)

arXiv.org Machine Learning

We propose a stochastic approximation (SA) based method with randomization of samples for policy evaluation using the least squares temporal difference (LSTD) algorithm. Our method results in an $O(d)$ improvement in complexity in comparison to regular LSTD, where $d$ is the dimension of the data. We provide convergence rate results for our proposed method, both in high probability and in expectation. Moreover, we also establish that using our scheme in place of LSTD does not impact the rate of convergence of the approximate value function to the true value function and hence a low-complexity LSPI variant that uses our SA based scheme has the same order of the performance bounds as that of regular LSPI. These rate results coupled with the low complexity of our method make it attractive for implementation in big data settings, where $d$ is large. Furthermore, we analyze a similar low-complexity alternative for least squares regression and provide finite-time bounds there. We demonstrate the practicality of our method for LSTD empirically by combining it with the LSPI algorithm in a traffic signal control application. We also conduct another set of experiments that combines the SA based low-complexity variant for least squares regression with the LinUCB algorithm for contextual bandits, using the large scale news recommendation dataset from Yahoo.


Variants of RMSProp and Adagrad with Logarithmic Regret Bounds

arXiv.org Artificial Intelligence

Adaptive gradient methods have become recently very popular, in particular as they have been shown to be useful in the training of deep neural networks. In this paper we have analyzed RMSProp, originally proposed for the training of deep neural networks, in the context of online convex optimization and show $\sqrt{T}$-type regret bounds. Moreover, we propose two variants SC-Adagrad and SC-RMSProp for which we show logarithmic regret bounds for strongly convex functions. Finally, we demonstrate in the experiments that these new variants outperform other adaptive gradient techniques or stochastic gradient descent in the optimization of strongly convex functions as well as in training of deep neural networks.


Ubisoft's next indie game 'Ode' is out in the UK

Engadget

A couple years ago, Ubisoft started an incubator at its Reflections Studio to make indie games -- the first of which, the delightful Grow Home, came out in early 2015. Now the same team has released a new title, the relaxing platformer'experience' Ode. Similar to the previous titles that came out of Reflections' incubator, Ode is simple. There's no HUD, hints, instructions or threats -- just exploration within its exploratory synaesthesia. In summary, it's a "musical exploration where you gradually bring a world to life through music and light," the game's producer Anne Langouriuex said in Ubisoft's blog post announcing Ode.


How Music Streaming Sites Can Compete For Users With Personalized Content

International Business Times

The global recorded music market grew by 5.9 percent last year. It was the fastest rate of growth since 1997 and was as a result of the shift from traditional CDs and portable devices to the ability to stream content anywhere, at any time. Yet despite an estimated 498 online music streaming services available in over 40 countries in 2007, many of these companies cease to exist today. This emphasizes the importance of building a clear growth strategy that can continuously appeal to a demographic that is yearning for instant and tailored music on demand. Today, brands across the globe are continually searching for fresh ways to connect and resonate with their audiences while striving to stand out from the competition in order to grow their business.


Furhat mannequin robots feel like 'they are alive'

Daily Mail - Science & tech

They are intended to make people feel more comfortable interacting with robots, but disembodied Furhat heads may have the opposite effect on some. The creepy creations, which use mannequins as their base, can be altered to take on the appearance of a range of computer generated characters. Designed to be'socially intelligent', their creator says they are so realistic that they feel'like they are alive.' They are intended to make people feel more comfortable interacting with robots, but disembodied Furhat heads may have the opposite effect on some. The creepy creations use mannequins as their base.