As the size and richness of available datasets grow larger, the opportunities for solving increasingly challenging problems with algorithms learning directly from data grow at the same pace. Consequently, the capability of learning algorithms to work with large amounts of data has become a crucial scientific and technological challenge for their practical applicability. Hence, it is no surprise that large-scale learning is currently drawing plenty of research effort in the machine learning research community. In this thesis, we focus on kernel methods, a theoretically sound and effective class of learning algorithms yielding nonparametric estimators. Kernel methods, in their classical formulations, are accurate and efficient on datasets of limited size, but do not scale up in a cost-effective manner. Recent research has shown that approximate learning algorithms, for instance random subsampling methods like Nystr\"om and random features, with time-memory-accuracy trade-off mechanisms are more scalable alternatives. In this thesis, we provide analyses of the generalization properties and computational requirements of several types of such approximation schemes. In particular, we expose the tight relationship between statistics and computations, with the goal of tailoring the accuracy of the learning process to the available computational resources. Our results are supported by experimental evidence on large-scale datasets and numerical simulations. We also study how large-scale learning can be applied to enable accurate, efficient, and reactive lifelong learning for robotics. In particular, we propose algorithms allowing robots to learn continuously from experience and adapt to changes in their operational environment. The proposed methods are validated on the iCub humanoid robot in addition to other benchmarks.

The objective of this work is to improve the accuracy of building demand forecasting . This is a more challenging t ask than grid level forecasting. For the said purpose, we develop a new technique called recurrent transform learning (RTL). The first one (RTL) is unsupervised; this is used as a feature extraction tool that is further fed into a regression model. Forecasting experiments have been carried out on three popular publicly available datasets. Both of our proposed techniques yield results superior to the state - of - the - art like long short term memory network, echo state network and sparse coding regression. Index Terms -- demand forecasting, dynamical model, load forecasting, transform learning . H E impor tance of electrical load forecasting is well known. The issue has gained even more significance with the advent of smartgrids, microgrids and smart buildings. An excellent review on this topic can be found in [1].

Various researchers have studied posterior inference of parameters in Bayesian mixture models [24, 42, 23], so that the statistical behavior of such models is relatively well-understood. In contrast, much less is known about the efficiency of different algorithms for sampling from the posterior distributions that arise from Bayesian mixture models. A standard approach for doing so is via some form of Markov Chain Monte Carlo (MCMC). Many different types of MCMC algorithms have been introduced for various types of Bayesian mixture models, including finite Bayesian mixture models [21, 49, 50, 26, 40], Dirichlet process mixture models [37, 41, 25, 28], and hierarchical and nested Dirichlet process models [52, 47]. Despite the plethora of possible MCMC methods, upper bounds on their mixing times are often challenging to establish. We refer the reader to the papers [27, 3, 55, 48, 57] for non-asymptotic upper bounds on mixing times for certain types of Bayesian models, different from those studied in this paper. In recent years, it has been increasingly common in the Bayesian literature to make use of a fractional likelihood--meaning an ordinary likelihood raised to some fractional power. Combining such a fractional likelihood with a prior distribution in the usual way leads to a class of posteriors known as power posterior or fractional posterior distributions. The power posterior distributions have been shown to have attractive properties in terms of robustness to mis-specification in Bayesian mixture models [39], and have been used in various applications 1 arXiv:1912.05153v1

We propose to reinterpret a standard discriminative classifier of p(y|x) as an energy based model for the joint distribution p(x,y). In this setting, the standard class probabilities can be easily computed as well as unnormalized values of p(x) and p(x|y). Within this framework, standard discriminative architectures may beused and the model can also be trained on unlabeled data. We demonstrate that energy based training of the joint distribution improves calibration, robustness, andout-of-distribution detection while also enabling our models to generate samplesrivaling the quality of recent GAN approaches. We improve upon recently proposed techniques for scaling up the training of energy based models and presentan approach which adds little overhead compared to standard classification training. Our approach is the first to achieve performance rivaling the state-of-the-artin both generative and discriminative learning within one hybrid model.

We propose a scalable Bayesian preference learning method for jointly predicting the preferences of individuals as well as the consensus of a crowd from pairwise labels. Peoples' opinions often differ greatly, making it difficult to predict their preferences from small amounts of personal data. Individual biases also make it harder to infer the consensus of a crowd when there are few labels per item. We address these challenges by combining matrix factorisation with Gaussian processes, using a Bayesian approach to account for uncertainty arising from noisy and sparse data. Our method exploits input features, such as text embeddings and user metadata, to predict preferences for new items and users that are not in the training set. As previous solutions based on Gaussian processes do not scale to large numbers of users, items or pairwise labels, we propose a stochastic variational inference approach that limits computational and memory costs. Our experiments on a recommendation task show that our method is competitive with previous approaches despite our scalable inference approximation. We demonstrate the method's scalability on a natural language processing task with thousands of users and items, and show improvements over the state of the art on this task. We make our software publicly available for future work.

This tutorial is part of the Machine learning for developers learning path. In this tutorial, we describe the basics of solving a classification-based machine learning problem, and give you a comparative study of some of the current most popular algorithms. In the open Notebook, click Run to run the cells one at a time. The rest of the tutorial follows the order of the Notebook. Classification is when the feature to be predicted contains categories of values.

In mammals, goal-directed and planning processes support flexible behaviour usable to face new situations or changed conditions that cannot be tackled through more efficient but rigid habitual behaviours. Within the Bayesian modelling approach of brain and behaviour, probabilistic models have been proposed to perform planning as a probabilistic inference. Recently, some models have started to face the important challenge met by this approach: grounding such processes on the computations implemented by brain spiking networks. Here we propose a model of goal-directed behaviour that has a probabilistic interpretation and is centred on a recurrent spiking neural network representing the world model. The model, building on previous proposals on spiking neurons and plasticity rules having a probabilistic interpretation, presents these novelties at the system level: (a) the world model is learnt in parallel with its use for planning, and an arbitration mechanism decides when to exploit the world-model knowledge with planning, or to explore, on the basis of an entropy-based confidence on the world model knowledge; (b) the world model is a hidden Markov model (HMM) able to simulate sequences of states and actions, thus planning selects actions through the same neural generative process used to predict states; (c) the world model learns the hidden causes of observations, and their temporal dependencies, through a biologically plausible unsupervised learning mechanism.

FL embodies the principles of focused data collection and minimization, and can mitigate many of the systemic privacy risks and costs resulting from traditional, centralized machine learning and data science approaches. Motivated by the explosive growth in FL research, this paper discusses recent advances and presents an extensive collection of open problems and challenges. Peter Kairouz and H. Brendan McMahan conceived, coordinated, and edited this work.

This paper investigates Frequentist consistency properties of the posterior distributions constructed via Generalized Variational Inference (GVI). A number of generic and novel strategies are given for proving consistency, relying on the theory of $\Gamma$-convergence. Specifically, this paper shows that under minimal regularity conditions, the sequence of GVI posteriors is consistent and collapses to a point mass at the population-optimal parameter value as the number of observations goes to infinity. The results extend to the latent variable case without additional assumptions and hold under misspecification. Lastly, the paper explains how to apply the results to a selection of GVI posteriors with especially popular variational families. For example, consistency is established for GVI methods using the mean field normal variational family, normal mixtures, Gaussian process variational families as well as neural networks indexing a normal (mixture) distribution.

ABSTRACT: T his paper aims at detecting an accurate position of the main entrance of the buildings. The proposed approach relies on the fact that the GPS signals drop significantly when the user enters a building. Moreover, as most of the public buildings provide Wi - Fi services, the W i - Fi received signal strength (RSS) can be utilized in order to detect the entrance of the buildings. The rationale behind this paper is that the GPS signals decrease as the user gets close to the main entrance and the Wi - Fi signal increases as the user ap proaches the main entrance. Several real experiments have been conducted in order to guarantee the feasibility of the proposed approach.