Bayesian Inference
Directional Statistics in Machine Learning: a Brief Review
The modern data analyst must cope with data encoded in various forms, vectors, matrices, strings, graphs, or more. Consequently, statistical and machine learning models tailored to different data encodings are important. We focus on data encoded as normalized vectors, so that their "direction" is more important than their magnitude. Specifically, we consider high-dimensional vectors that lie either on the surface of the unit hypersphere or on the real projective plane. For such data, we briefly review common mathematical models prevalent in machine learning, while also outlining some technical aspects, software, applications, and open mathematical challenges.
What is the classification of model that uses convolutiona filters with SVM/Bayes classifier • /r/MachineLearning
Sure, it's a neural net, although someone who felt that it wasn't could probably make that argument. Bottom line - there aren't a lot of fundamentalists who will care a lot about a strong line discriminating what is and is not an instance of machine learning method X. Using a convolutional network as, effectively, a hierarchical set of image filters has certainly been done. You might have some trouble training it with a top level model that had problematic derivatives, and so had weird backprop issues. Realistically, a lot of work has involved training a deep convolutional net on a task, then cutting off the top fully connected layer, and instead taking the inputs as features for another kind of classifier (usually an SVM) to squeeze a little extra performance.
Maximum Likelihood Decoding with RNNs - the good, the bad, and the ugly - The Stanford Natural Language Processing Group
Training Tensorflow's large language model on the Penn Tree Bank yields a test perplexity of 82. It depends on your personal taste. The high temperature sample displays greater linguistic variety, but the low temperature sample is more grammatically correct. Such is the world of temperature sampling - lowering the temperature allows you to focus on higher probability output sequences and smooth over deficiencies of the model. Temperature sampling works by increasing the probability of the most likely words before sampling.
Scalable Discrete Sampling as a Multi-Armed Bandit Problem
Chen, Yutian, Ghahramani, Zoubin
Drawing a sample from a discrete distribution is one of the building components for Monte Carlo methods. Like other sampling algorithms, discrete sampling suffers from the high computational burden in large-scale inference problems. We study the problem of sampling a discrete random variable with a high degree of dependency that is typical in large-scale Bayesian inference and graphical models, and propose an efficient approximate solution with a subsampling approach. We make a novel connection between the discrete sampling and Multi-Armed Bandits problems with a finite reward population and provide three algorithms with theoretical guarantees. Empirical evaluations show the robustness and efficiency of the approximate algorithms in both synthetic and real-world large-scale problems.
Probabilistic Graphical Models on Multi-Core CPUs using Java 8
Masegosa, Andres R., Martinez, Ana M., Borchani, Hanen
In this paper, we discuss software design issues related to the development of parallel computational intelligence algorithms on multi-core CPUs, using the new Java 8 functional programming features. In particular, we focus on probabilistic graphical models (PGMs) and present the parallelisation of a collection of algorithms that deal with inference and learning of PGMs from data. Namely, maximum likelihood estimation, importance sampling, and greedy search for solving combinatorial optimisation problems. Through these concrete examples, we tackle the problem of defining efficient data structures for PGMs and parallel processing of same-size batches of data sets using Java 8 features. We also provide straightforward techniques to code parallel algorithms that seamlessly exploit multi-core processors. The experimental analysis, carried out using our open source AMIDST (Analysis of MassIve Data STreams) Java toolbox, shows the merits of the proposed solutions.
5 skills You Need to Become a Machine Learning Engineer
The world is unquestionably changing in rapid and dramatic ways, and the demand for Machine Learning engineers is going to keep increasing exponentially. Now undoubtedly Machine Learning has arrived. To begin, there are two very important things that you should understand if you're considering a career as a Machine Learning engineer. You don't necessarily have to have a research or academic background. Second, it's not enough to have either software engineering or data science experience.
Sparse group factor analysis for biclustering of multiple data sources
Bunte, Kerstin, Leppäaho, Eemeli, Saarinen, Inka, Kaski, Samuel
Motivation: Modelling methods that find structure in data are necessary with the current large volumes of genomic data, and there have been various efforts to find subsets of genes exhibiting consistent patterns over subsets of treatments. These biclustering techniques have focused on one data source, often gene expression data. We present a Bayesian approach for joint biclustering of multiple data sources, extending a recent method Group Factor Analysis (GFA) to have a biclustering interpretation with additional sparsity assumptions. The resulting method enables data-driven detection of linear structure present in parts of the data sources. Results: Our simulation studies show that the proposed method reliably infers bi-clusters from heterogeneous data sources. We tested the method on data from the NCI-DREAM drug sensitivity prediction challenge, resulting in an excellent prediction accuracy. Moreover, the predictions are based on several biclusters which provide insight into the data sources, in this case on gene expression, DNA methylation, protein abundance, exome sequence, functional connectivity fingerprints and drug sensitivity.
Bayes' Theorem And Robot Arms Open Data Science Conferences
If you enjoyed Jesse's presentation at ODSC's last Boston Big Data Conference come to ODSC East this May to hear out his colleagues. Rather than start with the statement of Bayes' Theorem, I want to use an old math teacher trick (which I realize many students hate) of trying to derive it from scratch, without stating what we're trying to derive. Rather, we'll start by modifying a problem that I described in an earlier post on probability distributions1. Bayes' gives you a way of determining the probability that a given event will occur, or that a given condition is true, given your knowledge of another related event or condition. All the examples that I've read or heard about seemed somewhat contrived and unrelated to the sorts of data analysis I was interested in.
On Partial Information and Contradictions in Probabilistic Abstract Argumentation
Hunter, Anthony (University College London) | Thimm, Matthias (Universität Koblenz-Landau)
We provide new insights into the area of combining abstract argumentation frameworks with probabilistic reasoning. In particular, we consider the scenario when assessments on the probabilities of a subset of the arguments is given and the probabilities of the remaining arguments have to be derived, taking both the topology of the argumentation framework and principles of probabilistic reasoning into account. We generalize this scenario by also considering inconsistent assessments, i.e., assessments that contradict the topology of the argumentation framework. Building on approaches to inconsistency measurement, we present a general framework to measure the amount of conflict of these assessments and provide a method for inconsistent-tolerant reasoning.