NMF (version 0.2.2)

deviance: Distances and Objective Functions

Description

The NMF package defines methods for the generic deviance from the package stats, to compute approximation errors between NMF models and matrices, using a variety of objective functions.

nmfDistance returns a function that computes the distance between an NMF model and a compatible matrix.

Usage

deviance(object, ...)
  ## S3 method for class 'NMF':
deviance(object, y,
    method = c("", "KL", "euclidean"), ...)
  nmfDistance(method = c("", "KL", "euclidean"))
  ## S3 method for class 'NMFfit':
deviance(object, y, method, ...)
  ## S3 method for class 'NMFStrategy':
deviance(object, x, y, ...)

Arguments

y

a matrix compatible with the NMF model object, i.e. y must have the same dimension as fitted(object).

method

a character string or a function with signature (x="NMF", y="matrix", ...) that implements a distance measure between an NMF model x and a target matrix y, i.e. an objective function to use to compute the dev

...

extra parameters passed to the objective function.

x

an NMF model that estimates y.

object

an object for which the deviance is desired.

Value

• deviance returns a nonnegative numerical value

  nmfDistance returns a function with least two arguments: an NMF model and a matrix.

See Also

Other stats: deviance,NMF-method, hasTrack, residuals, residuals<-, trackError