| sufficientStatistics_Weighted.GaussianNIW | R Documentation |
For following Gaussian-NIW model structure:
mu,Sigma|m,k,v,S \sim NIW(m,k,v,S)
x|mu,Sigma \sim Gaussian(mu,Sigma)
Where NIW() is the Normal-Inverse-Wishart distribution, Gaussian() is the Gaussian distribution. See ?dNIW and dGaussian for the definitions of these distribution.
The sufficient statistics of a set of samples x (each row of x is a sample) and weights w are:
the effective number of samples N=sum(w)
the sample sum xsum = colSums(x*w)
the uncentered scatter matrix S = t(w*x)
## S3 method for class 'GaussianNIW' sufficientStatistics_Weighted(obj, x, w, foreach = FALSE, ...)
obj |
A "GaussianNIW" object. |
x, |
matrix, Gaussian samples, when x is a matrix, each row is a sample of dimension ncol(x). when x is a vector, x is length(x) samples of dimension 1. |
w |
numeric, sample weights. |
foreach |
logical, if foreach=TRUE, will return a list of sufficient statistics for each row of x, otherwise will return the sufficient statistics of x as a whole. |
... |
Additional arguments to be passed to other inherited types. |
If foreach=TRUE, will return a list of sufficient statistics for each row of x, otherwise will return the sufficient statistics of x as a whole.
Murphy, Kevin P. "Conjugate Bayesian analysis of the Gaussian distribution." def 1.22 (2007): 16.
Gelman, Andrew, et al. "Bayesian Data Analysis Chapman & Hall." CRC Texts in Statistical Science (2004).
GaussianNIW, sufficientStatistics.GaussianNIW
x <- rGaussian(10,mu = c(-1.5,1.5),Sigma = matrix(c(0.1,0.03,0.03,0.1),2,2)) obj <- GaussianNIW() #an GaussianNIW object w <- runif(10) sufficientStatistics_Weighted(obj=obj,x=x,w=w,foreach = FALSE) sufficientStatistics_Weighted(obj=obj,x=x,w=w,foreach = TRUE)