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Global Artificial Intelligence Market Worth 23.4 Billion by 2025 - Identify Key Investment
The report estimates that the Global Artificial Intelligence Market will reach a value of 23.4 Billion by 2025. It focuses on market trends, leading players, supply chain trends, technological innovations, key developments, and future strategies. The report provides comprehensive market assessment across the major geographies such as North America, Europe, Asia Pacific, Middle East, Latin America and Rest of the world. A details market analysis is included, with inputs derived from industry professionals across the value chain. A special focus has been made on 23 countries such as U.S., Canada, Mexico, U.K., Germany, Spain, France, Italy, China, Brazil, Saudi Arabia, South Africa, etc.
Power BI & Azure ML Better Together
There has been a lot of interest in the analytics community in visualizing the output of an Azure Machine Learning model inside Power BI. To add to the challenge, it would also be great to operationalize Azure ML models through the Power BI service. Imagine if you could have Power BI regularly bring in the latest output of your fraud model or the sentiment for recent Tweets about your products. The following tutorial will outline a proposed approach for doing just that. For the purpose of this tutorial we will assume your data is sitting inside an Azure SQL database.
Certificate in data science - University of Washington
This course is part of a certificate program. You can enroll in this course on a space available basis even though you are not a certificate student. Courses taken when you are not a certificate student don't automatically count toward earning a certificate. You will pay a course fee when you are notified of your eligibility to enroll. We will let you know whether you are accepted or not accepted into the course before the first class session.
Sequential Principal Curves Analysis
LASSICAL unsupervised learning such as Principal Components Analysis (PCA) and Independent Component Analysis (ICA) is useful to design artificial sensory systems and to understand the organization of natural sensory systems. On the artificial side, examples include representations/transforms for image coding [6]-[9] and image categorization [10], [11]. On the natural side, examples include the analysis of visual cortex [12]-[16]. PCA and ICA obtain basis of the space according to different optimization criteria. These basis functions can be interpreted as linear sensors: the projection of data onto these basis represents the response of the set of sensors. PCA defines a sensor hierarchy: for example, an image sensory system made out of principal directions with highest eigenvalues minimizes the image reconstruction error [6], [7]. In ICA, the basis is intended to provide responses as independent as possible, which is equivalent to design a sensory system that maximizes the transmitted information (infomax) [17], [18].
High Dimensional Multivariate Regression and Precision Matrix Estimation via Nonconvex Optimization
We propose a nonconvex estimator for joint multivariate regression and precision matrix estimation in the high dimensional regime, under sparsity constraints. A gradient descent algorithm with hard thresholding is developed to solve the nonconvex estimator, and it attains a linear rate of convergence to the true regression coefficients and precision matrix simultaneously, up to the statistical error. Compared with existing methods along this line of research, which have little theoretical guarantee, the proposed algorithm not only is computationally much more efficient with provable convergence guarantee, but also attains the optimal finite sample statistical rate up to a logarithmic factor. Thorough experiments on both synthetic and real datasets back up our theory.
Generalized Root Models: Beyond Pairwise Graphical Models for Univariate Exponential Families
Inouye, David I., Ravikumar, Pradeep, Dhillon, Inderjit S.
We present a novel k-way high-dimensional graphical model called the Generalized Root Model (GRM) that explicitly models dependencies between variable sets of size k > 2---where k = 2 is the standard pairwise graphical model. This model is based on taking the k-th root of the original sufficient statistics of any univariate exponential family with positive sufficient statistics, including the Poisson and exponential distributions. As in the recent work with square root graphical (SQR) models [Inouye et al. 2016]---which was restricted to pairwise dependencies---we give the conditions of the parameters that are needed for normalization using the radial conditionals similar to the pairwise case [Inouye et al. 2016]. In particular, we show that the Poisson GRM has no restrictions on the parameters and the exponential GRM only has a restriction akin to negative definiteness. We develop a simple but general learning algorithm based on L1-regularized node-wise regressions. We also present a general way of numerically approximating the log partition function and associated derivatives of the GRM univariate node conditionals---in contrast to [Inouye et al. 2016], which only provided algorithm for estimating the exponential SQR. To illustrate GRM, we model word counts with a Poisson GRM and show the associated k-sized variable sets. We finish by discussing methods for reducing the parameter space in various situations.
f-GAN: Training Generative Neural Samplers using Variational Divergence Minimization
Nowozin, Sebastian, Cseke, Botond, Tomioka, Ryota
Generative neural samplers are probabilistic models that implement sampling using feedforward neural networks: they take a random input vector and produce a sample from a probability distribution defined by the network weights. These models are expressive and allow efficient computation of samples and derivatives, but cannot be used for computing likelihoods or for marginalization. The generative-adversarial training method allows to train such models through the use of an auxiliary discriminative neural network. We show that the generative-adversarial approach is a special case of an existing more general variational divergence estimation approach. We show that any f-divergence can be used for training generative neural samplers. We discuss the benefits of various choices of divergence functions on training complexity and the quality of the obtained generative models.
Forecasting wind power - Modeling periodic and non-linear effects under conditional heteroscedasticity
Ziel, Florian, Croonenbroeck, Carsten, Ambach, Daniel
In this article we present an approach that enables joint wind speed and wind power forecasts for a wind park. We combine a multivariate seasonal time varying threshold autoregressive moving average (TVARMA) model with a power threshold generalized autoregressive conditional heteroscedastic (power-TGARCH) model. The modeling framework incorporates diurnal and annual periodicity modeling by periodic B-splines, conditional heteroscedasticity and a complex autoregressive structure with nonlinear impacts. In contrast to usually time-consuming estimation approaches as likelihood estimation, we apply a high-dimensional shrinkage technique. We utilize an iteratively re-weighted least absolute shrinkage and selection operator (lasso) technique. It allows for conditional heteroscedasticity, provides fast computing times and guarantees a parsimonious and regularized specification, even though the parameter space may be vast. We are able to show that our approach provides accurate forecasts of wind power at a turbine-specific level for forecasting horizons of up to 48 hours (short-to medium-term forecasts).
Bayesian Learning of Kernel Embeddings
Flaxman, Seth, Sejdinovic, Dino, Cunningham, John P., Filippi, Sarah
Kernel methods are one of the mainstays of machine learning, but the problem of kernel learning remains challenging, with only a few heuristics and very little theory. This is of particular importance in methods based on estimation of kernel mean embeddings of probability measures. For characteristic kernels, which include most commonly used ones, the kernel mean embedding uniquely determines its probability measure, so it can be used to design a powerful statistical testing framework, which includes nonparametric two-sample and independence tests. In practice, however, the performance of these tests can be very sensitive to the choice of kernel and its lengthscale parameters. To address this central issue, we propose a new probabilistic model for kernel mean embeddings, the Bayesian Kernel Embedding model, combining a Gaussian process prior over the Reproducing Kernel Hilbert Space containing the mean embedding with a conjugate likelihood function, thus yielding a closed form posterior over the mean embedding. The posterior mean of our model is closely related to recently proposed shrinkage estimators for kernel mean embeddings, while the posterior uncertainty is a new, interesting feature with various possible applications. Critically for the purposes of kernel learning, our model gives a simple, closed form marginal pseudolikelihood of the observed data given the kernel hyperparameters. This marginal pseudolikelihood can either be optimized to inform the hyperparameter choice or fully Bayesian inference can be used.
Conditional Dependence via Shannon Capacity: Axioms, Estimators and Applications
Gao, Weihao, Kannan, Sreeram, Oh, Sewoong, Viswanath, Pramod
We conduct an axiomatic study of the problem of estimating the strength of a known causal relationship between a pair of variables. We propose that an estimate of causal strength should be based on the conditional distribution of the effect given the cause (and not on the driving distribution of the cause), and study dependence measures on conditional distributions. Shannon capacity, appropriately regularized, emerges as a natural measure under these axioms. We examine the problem of calculating Shannon capacity from the observed samples and propose a novel fixed-$k$ nearest neighbor estimator, and demonstrate its consistency. Finally, we demonstrate an application to single-cell flow-cytometry, where the proposed estimators significantly reduce sample complexity.