Log likelihood functions

Description

Returns a log-likelihood for a given hyper2 object at a specific point

Usage

loglik(p, H, log = TRUE)
loglik_single(p,H,log=TRUE)
like_single_list(p,Lsub)
like_series(p,L,log=TRUE)

Arguments

Details

Function loglik() is a straightforward likelihood function. It can take a vector of length n=size(H) or size(H)-1; if given the vector \(p=\left(p_1,\ldots,p_{n-1}\right)\) it appends the fillup value, and then returns returns the (log) likelihood.

If p is a matrix, the rows are interpreted as probability points.

Function loglik_single() is a helper function that takes a single point in probability space. Functions like_single_list() and like_series() are intended for use with ggrl().

Note

Likelihood is defined up to an arbitrary multiplicative constant. Log-likelihood (also known as support) is defined up to an arbitrary additive constant.

Currently, function loglik() interprets elements of a probability vector according to their position in the vector; if given a named vector, the names are ignored. This might change in a future release.

Empty brackets are interpreted consistently: that is, zero whatever the probability vector (although the print method is not perfect).

Author(s)

Robin K. S. Hankin

See Also

maxp

Examples

data(chess)
loglik(c(1/3,1/3),chess)

loglik(rp(14,icons),icons)

## Not run:  # takes too long
like_series(masterchef_maxp,masterchef)
like_series(indep(equalp(masterchef)),masterchef)

## End(Not run)

W <- hyper2(pnames=letters[1:6])
W1 <- ggrl(W, 'a', letters[2:5],'f')              # 24-element list
W2 <- ggrl(W, c('a','b'), c('c','d'),c('e','f'))  # 2^3=8 element list

like_single_list(rep(1/6,5),W1)      # information from first observation
like_series(rep(1/6,5),list(W1,W2))  # information from both observations