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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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Ezcontour in Matlab missing contours

I've used the gmdistribution to fit data to a Gaussian mixture model. I wanted to plot a contour plot https://i.stack.imgur.com/d6Pdb.jpg where the contours are obviously missing. For a 1D problem I found fplot, but now I'm stumped.
Piotr Sokol
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mixture copula in R

I want to use mixture copula for reliability analysis， now ，with the help of a friend ，I've already finished it ‘RVMs_fitted’ 。now i want to perform the probability integral transformation （PIT），but the function of RVINEPIT can’t use，because…
HIteWIng
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Evaluating Gaussian Mixture model using a score metric?

I have 1D data (on column data). I used Gaussian Mixture Model (GMM) as a density estimation, using this implementation in Python: https://scikit-learn.org/stable/modules/generated/sklearn.mixture.GaussianMixture.html. By relying on AIC/BIC criteron…
MWH
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PYMC3 Mixture model: help understanding multiple variables model

Let's say I have a dataframe with 4 variable. I want to see if I can generate a posterior of gamma mixtures over all the variables, with the goal to find clusters for each observation. I'm guessing I will need some sort of multivariate gamma…
James Stirling
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Specifying number of trials, bootstrap

For an assignment, I am applying mixture modeling with the mixtools package on R. When I try to figure out the optimal amount of components with bootstrap. I get the following error Error in boot.comp(y, x, N = NULL, max.comp = 2, B = 5, sig = 0.05,…
daantheboss
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Fit a binomial mixture in flexmix - what am I doing wrong?

I'm trying to understand flexmix, and specifically what I am doing wrong trying to fit the simplest conceivable binomial mixture model (mixture of two intercept-only models). set.seed(42) data=data.frame(class=rbinom(1000,size=1,prob=0.3)) %>% # 30%…
Nicholas Root
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How to vectorize likelihood calculation under multiple parameters?

I am trying to implement a bernoulli mixture and was wondering how to vectorize the calculations correctly without looping. I have tried various versions of apply but can't get the desired output (dim = c(5,4,2). Should my component parameters be…
amerikashka
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Parameterizing mixture density network covariances in tensorflow

I'm trying to build an MDN to learn P(y | x) where both y and x have dimension D, with K components with full (non-diagonal) covariances. From the output of the hidden layers of the NN I need to construct the component means, weights and…
jalsing
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Hierarchical Mixture Model in Stan

I'm trying to implement a hierarchical mixture model in Stan that describes how performance on a task changes over time. In the model (see code below), there are three lower level parameters that are assumed to be drawn from a mixture of two normals…
Tim
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Fitting a mixture of gamma and normal distribution to data in R

I would like to fit a mixture of gamma and normal distribution to my data in R. The data: dput(A) 0.0838, 0.081, 0.0816, 0.0838, 0.0824, 0.0871, 0.0899, 0.0938, 0.099, 0.1018, 0.0998, 0.1, 0.0955, 0.0972 Based on the data I believe (by looking at…
Is_PhD
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Facenet: Using Ensembles of Face Embedding Sets

The Facenet is a deep learning model for facial recognition. It is trained for extracting features, that is to represent the image by a fixed length vector called embedding. After training, for each given image, we take the output of the second last…
Alireza Akhavan
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General Mixture Model with PyMC3

I am new to PyMC3 and I have been attempting to create a mixture of independent Poisson's using the following code: import pymc3 as pm import numpy as np from pymc3.distributions.continuous import Uniform from pymc3.distributions.discrete import…
Hugo
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Very large log probabilities from sklearn's BayesianGaussianMixture

I've been using python to experiment with sklearn's BayesianGaussianMixture (and with GaussianMixture, which shows the same issue). I fit the model with a number of items drawn from a distribution, then tested the model with a held out data set…
Dave Challis
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ggplot mixture model R

I have a dataset with numeric values and a categorical variable. The distribution of the numeric variable differs for each category. I want to plot "density plots" for each categorical variable so that they are visually below the entire density…
user3702510
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How to fit a finite mixture of Dirichlet distributions

I have a compositional sample and I would like to fit a finite mixture of Dirichlet distributions. To be more precise, consider the following example: library(gtools) set.seed(1) PROB = c(0.25, 0.15, 0.60) ALPHA = list( c(1,1,1), c(2,1,1), …
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