MAP.CatDP {bbricks} | R Documentation |
Generate the MAP estimate of "pi" in following model structure:
pi|alpha \sim DP(alpha,U)
x|pi \sim Categorical(pi)
where DP(alpha,U) is a Dirichlet Process on positive integers, alpha is the "concentration parameter" of the Dirichlet Process, U is the "base measure" of this Dirichlet process, it is an uniform distribution on all positive integers.Categorical() is the Categorical distribution. See dCategorical
for the definition of the Categorical distribution.
In the case of CatDP, x can only be positive integers.
The model structure and prior parameters are stored in a "CatDP" object.
The MAP estimate of pi is pi_MAP = argmax_pi p(pi|alpha,x).
## S3 method for class 'CatDP' MAP(obj, ...)
obj |
A "CatDP" object. |
... |
Additional arguments to be passed to other inherited types. |
numeric.
Teh, Yee W., et al. "Sharing clusters among related groups: Hierarchical Dirichlet processes." Advances in neural information processing systems. 2005.
x <- sample(1L:10L,size = 40,replace = TRUE) obj <- CatDP() posterior(obj = obj,ss = x) MAP(obj)