diri_norm {hyperdirichlet} | R Documentation |
Normalization constants for the Dirichlet and generalized Dirichlet distributions using computationally efficient methods
diri_norm(x) gd_norm(a,b)
x |
Vector of parameters in the Dirichlet distribution |
a,b |
Vectors of parameters in the generalized Dirichlet distribution |
Returns the normalization constant:
omitted: see a LaTeXed file
for the Dirichlet and
omitted: see a LaTeXed file
for the generalized Dirichlet.
The functions make use of the logarithmic form of the gamma and beta functions to avoid overflow
Robin K. S. Hankin
R. J. Connor and J. E. Mosimann 1969. “Concepts of independence for proportions with a generalization of the Dirichlet distribution”. Journal of the American Statistical Association, volume 64, number 325, pp194-206
diri_norm(runif(9)) gd_norm(1:3 , 3:1)