Bayesian Inference


A Geek's Guide to Machine Learning and Risk analytics and Decisioning Provenir

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Other costs to the merchant include direct fraud costs, cost of manual order review, cost of reviewing tools and cost of rejecting orders [4]. We will be looking at various AI detection methods including Artificial Neural Networks (ANN), Fuzzy Neural Networks (FNN), Bayesian Neural Networks (BNN) and Expert Systems. The processing of these data sets by banks and credit card issuers requires complex statistical algorithms to extract the raw quantitative data. The techniques used to detect fraud also fall into two primary classes – Statistical techniques (clustering, algorithms) and Artificial Intelligence (ANN, FNN, Data Mining) [8].


Numbers war: How Bayesian vs frequentist statistics influence AI

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In other words, infected people test positive 99 per cent of the time and healthy people test negative 99 per cent of the time. We also need a figure for the prevalence of the infection in the population; if we don't know it, we can start by guessing that half of the population is infected and half is healthy. But this line of reasoning ignores the fact that 1 per cent of the healthy people will test positive and, as the proportion of healthy people increases, the number of those healthy people who test as positive begins to overwhelm those who are infected and also test positive. In slightly more formal terms we would say that the number of false positives (healthy people being misdiagnosed) begins to overwhelm the true positives (infected people testing positive).



Bayesian Basics, Explained

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Andrew Gelman: Bayesian statistics uses the mathematical rules of probability to combines data with "prior information" to give inferences which (if the model being used is correct) are more precise than would be obtained by either source of information alone. You can reproduce the classical methods using Bayesian inference: In a regression prediction context, setting the prior of a coefficient to uniform or "noninformative" is mathematically equivalent to including the corresponding predictor in a least squares or maximum likelihood estimate; setting the prior to a spike at zero is the same as excluding the predictor, and you can reproduce a pooling of predictors thorough a joint deterministic prior on their coefficients. When Bayesian methods work best, it's by providing a clear set of paths connecting data, mathematical/statistical models, and the substantive theory of the variation and comparison of interest. Bayesian methods offer a clarity that comes from the explicit specification of a so-called "generative model": a probability model of the data-collection process and a probability model of the underlying parameters.


will wolf

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Edward is a probabilistic programming library that bridges this gap: "black-box" variational inference enables us to fit extremely flexible Bayesian models to large-scale data. To "pull us down the path," we build three models in additive fashion: a Bayesian linear regression model, a Bayesian linear regression model with random effects, and a neural network with random effects. To infer posterior distributions of the model's parameters conditional on the data observed we employ variational inference -- one of three inference classes supported in Edward. Thus far, we've been approximating the relationship between our fixed effects and response variable with a simple dot product; can we leverage Keras to make this relationship more expressive?


The Perceptron Algorithm explained with Python code

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To do this, we can train a Classifier with a'training dataset' and after such a Classifier is trained (we have determined its model parameters) and can accurately classify the training set, we can use it to classify new data (test set). Logistic Regression uses a functional approach to classify data, and the Naive Bayes classifier uses a statistical (Bayesian) approach to classify data. Classifiers which are using a geometrical approach are the Perceptron and the SVM (Support Vector Machines) methods. Although Support Vector Machines is used more often, I think a good understanding of the Perceptron algorithm is essential to understanding Support Vector Machines and Neural Networks.


CamDavidsonPilon/Probabilistic-Programming-and-Bayesian-Methods-for-Hackers

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Chapter 1: Introduction to Bayesian Methods Introduction to the philosophy and practice of Bayesian methods and answering the question, "What is probabilistic programming?" Chapter 2: A little more on PyMC We explore modeling Bayesian problems using Python's PyMC library through examples. Chapter 1: Introduction to Bayesian Methods Introduction to the philosophy and practice of Bayesian methods and answering the question, "What is probabilistic programming?" Chapter 2: A little more on PyMC We explore modeling Bayesian problems using Python's PyMC library through examples.


Introduction to Machine Learning & Face Detection in Python

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This course is about the fundamental concepts of machine learning, focusing on neural networks, SVM and decision trees. These topics are getting very hot nowadays because these learning algorithms can be used in several fields from software engineering to investment banking. Learning algorithms can recognize patterns which can help detect cancer for example or we may construct algorithms that can have a very very good guess about stock prices movement in the market. We will talk about Naive Bayes classification and tree based algorithms such as decision trees and random forests.


Everything that Works Works Because it's Bayesian: Why Deep Nets Generalize?

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We could not so far claim that deep networks trained with stochastic gradient descent are Bayesian. And it may be because SGD biases learning towards flat minima, rather than sharp minima. It turns out, (Hochreiter and Schmidhuber, 1997) motivated their work on seeking flat minima from a Bayesian, minimum description length perspective. Seeking flat minima makes sense from a minimum description length perspective.


19 MOOCs on Maths & Statistics for Data Science & Machine Learning

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In this course, you will learn the basic concepts of probability, random variables, distributions, Bayes Theorem, probability mass functions and CDFs, joint distributions and expected values. Once you are familiar with the basics, you will learn about advanced concepts Bernoulli and Binomial distributions, Geometric distribution, Negative Binomial distribution, Poisson distribution, Hypergeometric distribution and discrete uniform distribution. Prerequisites: Basic algebra, number system and elementary set theory. In this course, the first section covers basic topics like probability like conditional probability, probability distribution and Bayes Theorem.