Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [von-mises-distribution]

The von Mises distribution is a continuous distribution defined on the unit circle. The generalization to the $n$-sphere for $n>1$ is the von Mises-Fisher distribution.

The Wikipedia pages on the von Mises distribution and on the von Mises-Fisher distribution collect a lot of information.

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Sampling from von Mises-Fisher distribution in Python?

I am looking for a simple way to sample from a multivariate von Mises-Fisher distribution in Python. I have looked in the stats module in scipy and the numpy module but only found the univariate von Mises distribution. Is there any code available? I…
mic
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sample from a von Mises distribution by transforming a RV?

Is there a distribution $p$ that I can sample from, such that for $\epsilon \sim p$, and for closed-form deterministic function $g_{\mu,\kappa}$, $g_{\mu, \kappa}(\epsilon) \sim \mathrm{vonMises(\mu, \kappa)}$, for any $\mu\in[-\pi,\pi]$ and…
Jeff
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Analysis hierarchical circular mixture data

I have circular data such that multiple human participants were, each shown a color from a color wheel, asked to remember it for a "retention interval", then report it back by clicking a color wheel. Each participant was tested many times in each…
Mike Lawrence
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What transformations preserve the von Mises distribution?

The von Mises distribution is entirely defined on the circle with a density given by $$f(x) = (2\,\pi\, I_0(\kappa))^{-1} \exp(\kappa \cos(x-\mu))\ ,$$ where $x$ is in an arbitrary real interval of length $2\pi$, $I_0$ is the Bessel-I function of…
Igor
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Why does the von Mises-Fisher distribution need two parameters?

The von Mises-Fisher distribution has two parameters: the mean $\mu \in \mathbb{R}^p$ and concentration $\kappa \geq 0$, where $\mu$ is constrained to have unit norm. Why not instead define the distribution for one unconstrained parameter i.e. $y :=…
Rylan Schaeffer
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Estimating kappa of von Mises distribution

Is there a way to calculate an estimate of the parameter $\kappa$ from data for the von Mises distribution? It seems very easy to do in R, http://rgm2.lab.nig.ac.jp/RGM2/func.php?rd_id=CircStats:A1inv, but python doesn't have an A1inv function to…
Swiss Army Man
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Estimating von Mises Parameters for Angular Data

I want to model some angular data. Any input on how to incorporate the von Mises distribution and suggestions on appropriate priors in RJAGS for von Mises mean and concentration would be greatly appreciated.
Murali
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Von Mises distribution to detect outliers

I am working out the difference between two angles from a circle, and I work out the mean difference across 96 trials in 10 separate samples. In order to detect outliers for statistical analysis, Barnett & Lewis (Outliers in Statistical Data, 1984)…
velvetshelter
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How can I fit a normal (von Mises) distribution to discrete angular data?

This bears some explaining: I have a set of data from a psychophysics experiment where participants selected a response from a discrete set of 8 possible responses. These responses were actually colours, but they are equivalent to angles (taken from…
BC1
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How to get the estimated means and standard deviations of two overlapping circular normal distributions?

I have the following plot: Overlapping circular normal distributions I would like to estimate the means and standard deviations of the apparent overlapping normal distributions. This is slightly complicated by the fact that since the data is based…
Mark Solinski
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Skewness and kurtosis of VonMises distribution

I could not find a reference that has mentioned the skewness and kurtosis of a circular data that has Von Mises distribution. What are the values? and it is great if someone can introduce some references in this regard.
Aep
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Two sample Kuiper test for checking normality of circular data

I have circular data and want to check whether it is a normal (Von Mises) distribution or not. I do the following steps: Create a Von Mises distribution with the same mean and kappa as my main data. Use two sample Kuiper test to compare the two…
Aep
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Semicircular mean

I am running MCMC sampling to determine an angular parameter resulting in several thousand samples. The angle is restricted to $[0,\pi]$ as we cannot distinguish $\alpha$ and $\alpha+\pi$. For distributions close to 0° and 180° I am running in the…
Tyrion
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Circular distributions Kolmogorov-Smirnov vs. Watson test vs. Rayleigh test

I am interested in assessing whether my angular data distribution is satisfactorily described by a von Mises distribution. In scale data, one can potentially use a Kolmogorov-Smirnov test. However, with circular data, it is usual to use the Watson…
Murali
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2d KDE with one circular dimension

I have a 2d data set where one dimension is circular (direction and speed). I would like to create a kernel density estimate but am unsure how to create a kernel. One idea I had was to use a von mises distribution in one direction, a gaussian in the…
Dave
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