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Questions tagged [mixture-model]

In statistics, a mixture model is a probabilistic model that is formed by a combination of probabilistic models. For example, the Gaussian mixture model is the weighted sum of Gaussian distributions. Mixture models are mainly used in probabilistic clustering of data and modelling of unknown distributional shapes.

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Visualize fitted gaussian distributions from GMM model

I am trying to visualize the fitted gaussian distribution from a Gaussian Mixture Model and can't seem to figure it out. Here and here I have seen examples for visualizing the fitted distributions of a one-dimensional model and I don't figure out…
dubbbdan
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Trouble using normalmixEM with initial parameters in R for fitting a Gaussian mixture model

I am new to gaussian mixture models and I am trying to learn how to use normalmixEM in R. I have read the documentation and in order to learn more about how it works I am trying to fit a mixture model to a fake data set that I created, however I get…
Daniel López
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Complexity of sampling from mixture model

I have a model where state j among M states is chosen with probability p_j. The probability could be any real number. This specifies a mixture model over the M states. I can access p_j for all j in constant time. I want to make a large number (N) of…
Gabriel Mitchell
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Multivariate Dirichlet process mixtures for density estimation using pymc3

I want to extend the Austin's example on Dirichlet process mixtures for density estimationto the multivariate case. The first information about multivariate Gaussian mixture using pymc3 I have found is this issue at Github. People involved in the…
A. Berihuete
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GMM by fitgmdist in MATLAB gives different results when running all iterations at once or iteratively

I am designing a new algorithm which needs to partially run EM algorithm. I am using MATLAB's (R2015b) fitgmdist for this. I observe a difference between the solutions obtained by (1) running a large number of iterations at once and (2) running the…
Krrr
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How is the CDF ("pgamma") of The Average of 10 Samples from Two Gammas Derived?

Case I: One Gamma ( I can do this! ) shape<-shape*10 scale<-scale/10 p_value_average_of_10_draws<-1-pgamma(q=average_of_10_draws, shape=shape, scale=scale, lower.tail = TRUE, log.p = FALSE) Case II: Two Gammas (I can't do…
rwinkel2000
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changing default colours when using the plot function of the R package mixtools

I have a plotting problem with curves when using mixtools Using the following R code require(mixtools) x <- c(rnorm(10000,8,2),rnorm(10000,18,5)) xMix <- normalmixEM(x, lambda=NULL, mu=NULL, sigma=NULL) plot(xMix, which = 2, nclass=25) I get a nice…
user2085797
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Handling zero rows/columns in covariance matrix during em-algorithm

I tried to implement GMMs but I have a few problems during the em-algorithm. Let's say I've got 3D Samples (stat1, stat2, stat3) which I use to train the GMMs. One of my training sets for one of the GMMs has in nearly every sample a "0" for stat1.…
Evox33
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Removing insignificant variables from summary object in R

I am fitting a mixture of beta regressions using the betamix package in R. If I use the example given in the package with code: data("ReadingSkills", package = "betareg") set.seed(4040) rs_mix <- betamix(accuracy ~ iq, data = ReadingSkills, k = 3, …
Divi
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how to apply complex model outputs neatly to data.table by a factor

I am using the normalmixEM function (algorithim) in R over a data.table object. It is a simple procedure to run it over the full table. This outputs a mixEM list object, in which the $posterior item is the most interest. I can map that back to the…
DaveRGP
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Matlab: EM for Gaussian Mixture Models without gmdistribution

I have to train a Gaussian Mixture model using four components on a given dataset. The set is three dimensional and contains 300 samples. The problem is that I cannot check for convergence using the log-likelihood because it is -Inf. This results…
evolved
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Images not loading on local view - mixture

I want to load images stored in respective subdirectories of html file for eg in images/ folder where my index.html file is located. when i tried to show images with this tag study all time this…
akshay bhange
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Clustering an image using Gaussian mixture models

I want to use GMM(Gaussian mixture models for clustering a binary image and also want to plot the cluster centroids on the binary image itself. I am using this as my reference: http://in.mathworks.com/help/stats/gaussian-mixture-models.html This…
ninja
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Mixture model predictive distributions in scikit-learn

I distilled a problem I am having with mixture modelling in scikit learn to the following 1D example. Simply fitting a mixture model to a 1D density. I'm experiencing good performance using the simple GMM, but odd behaviour using the Variational or…
Mark van der Wilk
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R - Fitting a Gaussian mixture for weighted observations

I've been trying to fit a Gaussian Mixture Model (GMM) for a univariate distribution where each observation has an assigned weight (from 0 to 1). Assigning weights can be easily done for the basic 'density' function (from 'stats'), but I could not…
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