Hypothesis test for von Mises-Fisher distribution over Kent distribution | R Documentation |
The null hypothesis is whether a von Mises-Fisher distribution fits the data well, where the altenrative is that Kent distribution is more suitable.
fishkent(x, B = 999)
x |
A numeric matrix containing the data as unit vectors in Euclidean coordinates. |
B |
The number of bootstrap re-samples. By default is set to 999. If it is equal to 1, no bootstrap is performed and the p-value is obtained throught the asymptotic distribution. |
Essentially it is a test of rotational symmetry, whether Kent's ovalness parameter (beta) is equal to zero. This works for spherical data only.
This is an "htest"class object. Thus it returns a list including:
statistic |
The test statistic value. |
parameter |
The degrees of freedom of the test. If bootstrap was employed this is "NA". |
p.value |
The p-value of the test. |
alternative |
A character with the alternative hypothesis. |
method |
A character with the test used. |
data.name |
A character vector with two elements. |
Michail Tsagris.
R implementation and documentation: Michail Tsagris mtsagris@uoc.gr.
Rivest L. P. (1986). Modified Kent's statistics for testing goodness of fit for the Fisher distribution in small concentrated samples. Statistics & Probability Letters, 4(1): 1–4.
iagesag, pc.test, vmf.mle, kent.mle
x <- rvmf(100, rnorm(3), 15)
fishkent(x)
fishkent(x, B = 1)
iagesag(x)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.