ea_multiGaussian_DL_PT: Diffusion probability for the Exact Algorithm for Langevin...

View source: R/multivariate_Gaussian_fusion.R

ea_multiGaussian_DL_PTR Documentation

Diffusion probability for the Exact Algorithm for Langevin diffusion for multivariate tempered Gaussian distribution

Description

Simulate Langevin diffusion using the Exact Algorithm where pi = multivariate tempered Gaussian distribution

Usage

ea_multiGaussian_DL_PT(
  x0,
  y,
  s,
  t,
  dim,
  mu,
  inv_Sigma,
  inv_Sigma_Z = transform_mats$to_X %*% inv_Sigma %*% transform_mats$to_X,
  beta,
  precondition_mat,
  transform_mats,
  diffusion_estimator = "Poisson",
  beta_NB = 10,
  gamma_NB_n_points = 2,
  logarithm
)

Arguments

x0

start value (vector of length dim)

y

end value (vector of length dim)

s

start time

t

end time

dim

dimension

mu

vector of length dim for mean

inv_Sigma

dim x dim inverse covariance matrix

beta

real value

precondition_mat

precondition matrix (if non-identity matrix, it should be the estimated covariance matrix, i.e. a matrix close to solve(inv_Sigma) - could run into problems if this is not the case since a trick is used to compute the bounds to avoid evaluating phi at 3^d points)

transform_mats

list of transformation matrices where transform_mats$to_Z is the transformation matrix to Z space and transform_mats$to_X is the transformation matrix to X space

diffusion_estimator

choice of unbiased estimator for the Exact Algorithm between "Poisson" (default) for Poisson estimator and "NB" for Negative Binomial estimator

beta_NB

beta parameter for Negative Binomial estimator (default 10)

gamma_NB_n_points

number of points used in the trapezoidal estimation of the integral found in the mean of the negative binomial estimator (default is 2)

logarithm

logical value to determine if log probability is returned (TRUE) or not (FALSE)

Value

acceptance probability of simulating Langevin diffusion with pi = multivariate tempered Gaussian distribution


rchan26/hierarchicalFusion documentation built on Sept. 11, 2022, 10:30 p.m.