| MAP.CatDirichlet | R Documentation |
Generate the MAP estimate of "pi" in following Categorical-Dirichlet structure:
pi|alpha \sim Dir(alpha)
x|pi \sim Categorical(pi)
Where Dir() is the Dirichlet distribution, Categorical() is the Categorical distribution. See ?dDir and dCategorical for the definitions of these distribution.
The model structure and prior parameters are stored in a "CatDirichlet" object.
MAP is pi_MAP = argmax p(pi|alpha,x).
## S3 method for class 'CatDirichlet' MAP(obj, ...)
obj |
A "CatDirichlet" object. |
... |
Additional arguments to be passed to other inherited types. |
A numeric vector, the MAP estimate of "pi".
Murphy, Kevin P. Machine learning: a probabilistic perspective. MIT press, 2012.
CatDirichlet
obj <- CatDirichlet(gamma=list(alpha=rep(1,26),uniqueLabels = letters)) x <- sample(letters,size = 20,replace = TRUE) w <- runif(20) posterior(obj=obj,ss=x,w=w) MAP(obj)