Questions tagged [bayesian]

Bayesian (after Thomas Bayes) refers to methods in probability and statistics that involve quantifying uncertainty about parameter or latent variable estimates by incorporating both prior and observed information. Bayesian modeling, inference, optimization, and model comparison techniques are on topic. A programming element is expected; theoretical/methodological questions should go to https://stats.stackexchange.com.

Overview

Bayesian inference is a method of statistical inference which uses Bayes' theorem - named after Thomas Bayes (1702-1761) - to quantify the uncertainty of parameters or latent variables. The statement of Bayes' theorem in Bayesian inference is

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Here θ represents the parameters to be inferred and d the data. P(θ|d) is the posterior probability and P(d|θ) is the likelihood function. P(θ) is the prior: a function encoding previous beliefs about θ within a model appropriate for the data. P(d) is a normalization factor.

The formula is used as an updating procedure: as more data become available, the posterior can be updated successively. In the first instance, the prior must be specified by the user. In later updates, the prior is usually chosen to be the posterior from a previous updating procedure.

References

The following threads contain lists of references:

The following journals are dedicated to research in Bayesian statistics:

Tag usage

Questions on tag should be about implementation and programming problems, not about the statistical or theoretical properties of the technique. Consider whether your question might be better suited to Cross Validated, the StackExchange site for statistics, machine learning and data analysis.

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Persistence on Java CI-Bayes object

Has anyone ever persisted a training set for CI-Bayes? I have sample code from this site: http://www.theserverside.com/news/thread.tss?thread_id=49773 here is the code: FisherClassifier fc=new FisherClassifierImpl(); fc.train("The quick brown fox…
wlindner
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Classifying Multinomial Naive Bayes Classifier with Python Example

I am looking for a simple example on how to run a Multinomial Naive Bayes Classifier. I came across this example from StackOverflow: Implementing Bag-of-Words Naive-Bayes classifier in NLTK import numpy as np from nltk.probability import…
Cryssie
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Using a Naive Bayes Classifier to classify tweets: some problems

Using, amongst other sources, various posts here on Stackoverflow, I'm trying to implement my own PHP classier to classify tweets into a positive, neutral and negative class. Before coding, I need to get the process straigt. My train-of-thought and…
Pr0no
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Calculate a weighted (Bayesian) average score/index in stored procedure?

I have an MS SQL Server 2008 database where I store places that serve food (cafés, restaurants, diners etc.). On a web site connected to this database people can rate the places on a scale from 1 to 3. On the web site there's a page where people…
tkahn
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Ensemble learning, multiple classifier system

I am trying to use a MCS (Multi classifier system) to do some better work on limited data i.e become more accurate. I am using K-means clustering at the moment but may choose to go with FCM (Fuzzy c-means) with that the data is clustered into…
G Gr
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OpenBUGS: missing value in Bernoulli distribution

I'm trying to model the observation "time" as random variable with OpenBUGS via R (R2OpenBUGS). If all the observation times are available (no NA's) everything works, but if I set one of the times to NA, nothing happens. I tested the same code with…
Jouni Helske
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Two-parameter Bayesian credibility Interval

How can I determine the confidence/credibility intervals for the posterior estimates of a multi-parameter model? I can get the confidence interval for each parameter separately. (Currently using bayestestR, but I don't mind using something…
Mich55
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Combining periodic and aperiodic kernels in sklearn GPR

I am using the scikit-learn Python library to perform Bayesian optimization (on top of Gaussian process regression) on a function which takes seven inputs. Four of these inputs represent physical angles, so the Gaussian kernel should be periodic in…
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pymc3 using start value for LKJCholeskyCov gives Bad initial energy error

When I try to give initial start values in for the standard deviations of LKJCholeskyCov I get a bad initial energy error in pymc3. Below, the first code runs fine. But the second will give you that error. I believe I am doing something wrong in…
ilyas
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what is the kappa variable (BayesianOptimization)

I read some posts and tutorials about BayesianOptimization and I never saw explanation about kappa variable. What is the kappa variable ? How can it help us ? How this values can influence the BayesianOptimization process ?
Boom
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PyMC3 - coal mining disaster example - questions re: adding a second mine

I'm playing around with PyMC3, trying to fit a modified version of the mining disaster switchpoint model in the PyMC3 documentation. Suppose you had two coal-mines (mine1 and mine2), each with similar disaster counts for the same range of…
Sham Doran
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Change point package in R using Reversible-Jump MCMC Bayesian approach

I am looking for a way (or at least an R package) to perform Bayesian changepoint analysis with Reversible-jump MCMC approach. I will apply this for detecting changepoints in Typhoon time series. This is my reference paper:…
Lyndz
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Extract learned NN posterior weight distribution parameters from DenseVariational layer

I also posted this question in the tensorflow probability Github issues: https://github.com/tensorflow/probability/issues/892 I'm using Tensorflow 2.1.0 and tensorflow-probability 0.9.0 in python 3.6.8. I'm working with a Tensorflow Probability…
Jed
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Recovering sine function paramters in PyMC3

I am unable to understand why the following code is not able to recover the paramters of the model. The same method was able to recover the parameters in a quadratic polynomial quite well. Please help. def sin(a,b,c,d,x): return a +…
Ayush Sahu
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Adding an extra factor (number of clicks) to a Bayesian ranking system

I run a music website for amateur musicians where we have a rating system based on a score out of 10, which is then calculated into an overall score out of 100. We have a "credibility" points system for users which directly influences the average…
Marc
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