Questions tagged [gamma-distribution]

Anything related to the gamma probability distribution, i.e. a continuous probability distribution whose probability density function is connected to the "gamma function". DO NOT USE this tag for questions about the gamma function, use the [gamma-function] tag instead.

Anything related to the gamma probability distribution, i.e. a continuous probability distribution whose probability density function is connected to the gamma function.

If a variable X follows a gamma distribution with shape parameter k>0 and scale parameter θ, then it has probability density function:

enter image description here

It follows that E(X)=kθ and Var(X)=kθ². In some texts, the gamma distribution is parameterized instead by the rate parameter, which is the reciprocal of the scale parameter: β=1/θ.

DO NOT USE this tag for questions about the gamma function, use the tag instead.

See Wikipedia page on the gamma distribution.


Tag Usage

Questions on 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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Setting parameters for gamma_distribution using boost

I am trying to use the Gamma distribution from Boost 1.5. Now I want the value of k and theta to be 4 and .5 respectively. But I get a compile error whenever I set the value of theta < 1. /usr/local/include/boost/random/gamma_distribution.hpp:118:…
freeborn
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How do you simulate an Erlang(k) variable using a programming language?

I have a college project in which I need to create a program which simulates an Erlang(k) variable. I am not talking about the Erlang language, it's about a standard Gamma(0,1,k), k ϵ N+. I appreciate if someone can help me out or give me advice on…
K33p3r
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How do plot mixed distributions?

I would like to generated a mix of five Gamma's distribution where r=3, lambda_i=1/i and theta_i= i/15 while i is in {1, 2 , 3, 4, 5}. Later I would like to plot them to show the results. I performed some code to generate one…
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How to do Gamma Distribution in Python?

So when using excel there is a function for gamma distribution function over there, I'm doing =GAMMADIST(B2,$K$2,$K$3, TRUE) which is nothing but GAMMADIST(x, alpha, beta, cumulative), here B2 is nothing but my first value of data, K2 and K3 are my…
Akilesh
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fitting a gamma variate curve to a set of data points in c++

I have an array of values (concentration values), with each value taken at a different time point. I need to fit a gamma-variate curve (formula is in the picture below) to these values (i.e. find alpha and beta such that the curve best fits those…
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Matlab Error: Index in Position 1 exceeds array bounds

I am attempting to create a gamma distribution in MATLAB; however, I keep receiving the error: Index in Position 1 exceeds array bounds (must not exceed 100). Assuming I am reading this correctly, it is referring to variable M that is simply =…
TryingToMath
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How do I output a probability density for gamma distribution at a specific value x? In C++

How do I output the probability density of a gamma distribution at a specific value x? (also the cdf, if possible!) Thanks!
rnt88
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R codes for AIC in distribution fitting

I have fitted the Weibull, lognormal and Gamma distributions to my claim amount data using the fitdistr in R. I want to choose which one fits my sample data the best using the AIC in R. How do I proceed?
user3309969
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Creating a Noisy Image and Removing Noise Using randg Gamma Law in Matlab?

I want to add Multiplicative Gamma Noise to a image using "randg" function in Matlab and remove that noise. We have to keep in mind that the noise should have mean 1 and level 4. It should follow Gamma law ( with Gamma Probability Distribution…
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