Questions tagged [fitting]

The process of fiting some statistical model to a particular set of data. Mostly done on a computer, and using varied numerical methods such as optimization or numerical integration, or simulation.

566 questions
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How to fit a Beta-Binomial Distribution to a dataset [duplicate]

I have a data set which is defined over positive integers and I have reasons to believe it follows a beta-binomial distribution. I am aware there is the ...
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Is there a difference in finding p-value using likelihood ratio vs minimum deviance statistic?

I am trying to fit my data to a distribution and find the fit parameters and associated p-value. If I use the -2-log likelihood ratio, or G-test, vs the minimum deviance method, will I get different p-...
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How to choose some discrete probability distribution to fit a target discrete probability distribution? [closed]

I have a set of vectors, each of which represents a discrete probability distribution, now I want to use some of them to simulate a certain discrete probability distribution. For instance, the ...
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Should I subtract lower bound from Gamma distributed data before estimating distribution parameters?

I have some real world data that reflects waiting time in a system. As it's about waiting times I assume it's Gamma distributed and visual check (histogram overlaid by a fitted Gamma PDF) shows no ...
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What model/significance test should I use to see if there's any significance between male and female sexual dimorphism on temperature over time?

In my lab I need to test if there's an significance between male and female sexual dimorphism on body temperature over 40 minutes. The temperature is simulated with a heat lamp and is turned on at 0 ...
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How to calculate “start” value for fitdist function for a Tracy-Widom distribution?

I have a data with 100 million data points, and I'm trying to make a Tracy-Widom distribution fit to this data using the following R script: ...
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How to fit a superimposed distribution (\eg a Gaussian distribution + a Uniform distribution)

Suppose we have a set of independent observations of a random variable X, which is a Superimposition of two mutual independent random variables (i.e. X = Y + Z), Y follows a uniform distribution, ...
191 views

R - how to estimate shape and scale parameters of Weibull distribution for claims development factors

I have a set of insurance data. Development factors fall with period, so follow Weibull distribution. I want to estimate Weibull parameters and smooth Development Factors. If I estimate parameters of ...
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Fitting wrong copula type to a real data set

I have developed a new mixture copula model. This model overcomes some limitation of copula models. I tested my new model on a simulation data. The model shows a superior result. My supervisor asked ...
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Inferring GMM parameters with Gibbs Sampling

On my book, "Machine Learning A Probabilistic Approach". It's stated that is straightforward to derive a Gibbs sampling algorithm to fit a mixture model, especially if we use conjugate priors. So ...
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How do I fit a cumulative Gaussian distribution in R? [closed]

I am trying to fit a cumulative Gaussian distribution function to my data, but I'm not sure how to do this. From what I understand, the fitting process tries to find the mean and standard deviation of ...
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Model fit for StMoMo

As a statistics newbie, I am trying to model mortality. I grabbed majority of the code from the package Vignette, and fitted the data. However, model fit does not seem to be great in my reproducible ...
52 views

Compute log-likelihood from sum of squares?

I have fit a 2D Gaussian to a surface in Matlab and need to compute the log-likelihood of this fit. Can One use the sum of squares between the Gaussian model and the actual surface to compute the log-...