Chatbots are on the rise, but what are they and why is everyone talking about (and to) them? Facebook has just rolled out support for bots on its Messenger platform. Meanwhile, Microsoft has described chatbots as the "new apps" with chief executive Satya Nadella saying that they "unlock conversation as a platform". The BBC "created" its own one-off chatbot to answer some of the burning questions you may have about this latest technology. What can I help you with Jane?

Something is wrong in the way ML is being taught to developers. Most ML teachers like to explain how different learning algorithms work and spend tons of time on that. For a beginner who wants to start using ML, being able to choose an algorithm and set parameters looks like the #1 barrier to entry, and knowing how the different techniques work seems to be a key requirement to remove that barrier. Many practitioners argue however that you only need one technique to get started: random forests. Other techniques may sometimes outperform them, but in general, random forests are the most likely to perform best on a variety of problems (see Do we Need Hundreds of Classifiers to Solve Real World Classification Problems?), which makes them more than enough for a developer just getting started with ML.

However, if the argument to exp(wT x) is large enough to cause overflow, wouldn't that also be the case for standard binary logistic regression as well, since negative-log-likelihood in that case contains the sigmoid function, which also has exp(wT x)? However, I don't think log-sum-exp can be applied to binary logistic regression, right?

Mauro Maggioni has been named the Bloomberg Distinguished Professor of Data Intensive Computation at Johns Hopkins in the Krieger School of Arts and Sciences' Department of Mathematics and the Whiting School of Engineering's Department of Applied Mathematics and Statistics. He will join Johns Hopkins from Duke University, where in 2012 he was promoted from assistant professor to full professor of mathematics, electrical and computer engineering, and computer science. Maggioni is the 20th Bloomberg Distinguished Professor appointed across Johns Hopkins. The professorships are supported by a 350 million gift to the university by Johns Hopkins alumnus, philanthropist, and three-term New York City Mayor Michael R. Bloomberg. The majority of this gift is dedicated to creating 50 new interdisciplinary professorships, galvanizing people, resources, research, and educational opportunities to address major world problems.

Sleep is a naturally recurring state of mind characterized by altered consciousness, relatively inhibited sensory activity, inhibition of nearly all voluntary muscles, and reduced interactions with surroundings.[1] It is distinguished from wakefulness by a decreased ability to react to stimuli, but is more easily reversed than the state of hibernation or of being comatose. Mammalian sleep occurs in repeating periods, in which the body alternates between two highly distinct modes known as non-REM and REM sleep. REM stands for "rapid eye movement" but involves many other aspects including virtual paralysis of the body. During sleep, most systems in an animal are in an anabolic state, building up the immune, nervous, skeletal, and muscular systems. Sleep in non-human animals is observed in mammals, birds, reptiles, amphibians, and fish, and, in some form, in insects and even in simpler animals such as nematodes. The internal circadian clock promotes sleep daily at night in diurnal species (such as humans) and in the day in nocturnal organisms (such as rodents). However, sleep patterns vary widely among animals and among different individual humans. Industrialization and artificial light have substantially altered human sleep habits in the last 100 years.[2] The diverse purposes and mechanisms of sleep are the subject of substantial ongoing research.[3] Sleep seems to assist animals with improvements in the body and mind. A well-known feature of sleep in humans is the dream, an experience typically recounted in narrative form, which resembles waking life while in progress, but which usually can later be distinguished as fantasy. Sleep is sometimes confused with unconsciousness, but is quite different in terms of thought process. Humans may suffer from a number of sleep disorders. These include dyssomnias (such as insomnia, hypersomnia, and sleep apnea), parasomnias (such as sleepwalking and REM behavior disorder), bruxism, and the circadian rhythm sleep disorders. In mammals and birds, sleep is divided into two broad types: rapid eye movement (REM sleep) and non-rapid eye movement (NREM or non-REM sleep). Each type has a distinct set of physiological and neurological features associated with it. REM sleep is associated with dreaming, desynchronized and faster brain waves, loss of muscle tone,[4] and suspension of homeostasis[citation needed]. REM and non-REM sleep are so different that physiologists classify them as distinct behavioral states. In this view, REM, non-REM, and waking represent the three major modes of consciousness, neural activity, and physiological regulation.[5]

GettyFacebook CEO Mark Zuckerberg's 2016 New Years resolution is to create a virtual assistant for his home. Facebook is investing heavily in what many in the tech industry believe to be the next frontier of innovation, artificial intelligence. The largest social network on earth has a division of AI experts it calls FAIR. There's also a separate team called Applied Machine Learning, which focuses on "giving people communication superpowers through AI." Facebook clearly believes that AI is important to the company's future. Its employees are running 50x more AI experiments per day compared to last year.

In machine learning, the problem of classification entails correctly identifying to which class or group a new observation belongs, by learning from observations whose classes are already known. In what follows, I will build a classification experiment in Azure ML Studio to predict wine quality based on physicochemical data. Several classification algorithms will be applied on the data set and the performance of these algorithms will be compared. I will also present a tutorial on how to do similar exercise using MRS (Microsoft R Server, formerly Revolution R Enterprise). I will use wine quality data set from the UCI Machine Learning Repository.

Let ${\mathcal S}_m$ be the set of all $m\times m$ density matrices (Hermitian positively semi-definite matrices of unit trace). Consider a problem of estimation of an unknown density matrix $\rho\in {\mathcal S}_m$ based on outcomes of $n$ measurements of observables $X_1,\dots, X_n\in {\mathbb H}_m$ (${\mathbb H}_m$ being the space of $m\times m$ Hermitian matrices) for a quantum system identically prepared $n$ times in state $\rho.$ Outcomes $Y_1,\dots, Y_n$ of such measurements could be described by a trace regression model in which ${\mathbb E}_{\rho}(Y_j|X_j)={\rm tr}(\rho X_j), j=1,\dots, n.$ The design variables $X_1,\dots, X_n$ are often sampled at random from the uniform distribution in an orthonormal basis $\{E_1,\dots, E_{m^2}\}$ of ${\mathbb H}_m$ (such as Pauli basis). The goal is to estimate the unknown density matrix $\rho$ based on the data $(X_1,Y_1), \dots, (X_n,Y_n).$ Let $$ \hat Z:=\frac{m^2}{n}\sum_{j=1}^n Y_j X_j $$ and let $\check \rho$ be the projection of $\hat Z$ onto the convex set ${\mathcal S}_m$ of density matrices. It is shown that for estimator $\check \rho$ the minimax lower bounds in classes of low rank density matrices (established earlier) are attained up logarithmic factors for all Schatten $p$-norm distances, $p\in [1,\infty]$ and for Bures version of quantum Hellinger distance. Moreover, for a slightly modified version of estimator $\check \rho$ the same property holds also for quantum relative entropy (Kullback-Leibler) distance between density matrices.

In the biclustering problem, we seek to simultaneously group observations and features. While biclustering has applications in a wide array of domains, ranging from text mining to collaborative filtering, the problem of identifying structure in high dimensional genomic data motivates this work. In this context, biclustering enables us to identify subsets of genes that are co-expressed only within a subset of experimental conditions. We present a convex formulation of the biclustering problem that possesses a unique global minimizer and an iterative algorithm, COBRA, that is guaranteed to identify it. Our approach generates an entire solution path of possible biclusters as a single tuning parameter is varied. We also show how to reduce the problem of selecting this tuning parameter to solving a trivial modification of the convex biclustering problem. The key contributions of our work are its simplicity, interpretability, and algorithmic guarantees - features that arguably are lacking in the current alternative algorithms. We demonstrate the advantages of our approach, which includes stably and reproducibly identifying biclusterings, on simulated and real microarray data.

Statistical machine learning plays an important role in modern statistics and computer science. One main goal of statistical machine learning is to provide universally consistent algorithms, i.e., the estimator converges in probability or in some stronger sense to the Bayes risk or to the Bayes decision function. Kernel methods based on minimizing the regularized risk over a reproducing kernel Hilbert space (RKHS) belong to these statistical machine learning methods. It is in general unknown which kernel yields optimal results for a particular data set or for the unknown probability measure. Hence various kernel learning methods were proposed to choose the kernel and therefore also its RKHS in a data adaptive manner. Nevertheless, many practitioners often use the classical Gaussian RBF kernel or certain Sobolev kernels with good success. The goal of this short note is to offer one possible theoretical explanation for this empirical fact.