normexp {limma}R Documentation

Normal + Exponential Log-Likelihood

Description

Marginal log-likelihood of foreground values for normal + exponential model and its derivatives. These functions are called by normexp.fit and are not normally called directly by the user.

Usage

normexp.m2loglik(par,x)
normexp.grad(par,x)

Arguments

par numeric vector of parameters
x numeric vector of (background corrected) intensities

Details

The parameter vector par holds the normal mean, the normal log-standard deviation and the exponential mean.

Computes minus twice the log-likelihood based on the $normal(μ,σ^2)+exponential(α)$ convolution model for the foreground intensities. The elements of par are $μ$, $log(σ)$ and $log(α)$.

Value

normexp.m2loglik returns a numeric scalar holding minus-twice the log-likelihood. normexp.grad returns a numeric vector holding the derivatives with respect to the elements of par.

Author(s)

Jeremy Silver and Gordon Smyth

See Also

An overview of background correction functions is given in 04.Background.


[Package limma version 2.4.7 Index]