OpenMx (version 2.3.1)

mxFitFunctionGREML: Create MxFitFunctionGREML Object

Description

This function creates a new MxFitFunctionGREML object.

Usage

mxFitFunctionGREML(dV=character(0))

Arguments

dV

Vector of character strings; defaults to a character vector of length zero. If a value of non-zero length is provided, it must be a named character vector. This vector's names must be the labels of free parameters in the model. The vector's el

Value

• Returns a new object of class MxFitFunctionGREML.

Details

Making effective use of argument dV will usually require a custom mxComputeSequence(). The derivatives of the REML loglikelihood function with respect to parameters can be internally computed from the derivatives of the 'V' matrix supplied via dV. These loglikelihood derivatives will be valid as long as (1) the derivatives of 'V' evaluate to symmetric matrices the same size as 'V,' and (2) the model contains no MxConstraints. Internally, the derivatives of the 'V' matrix are assumed to be symmetric, and the elements above their main diagonals are ignored.

References

The OpenMx User's guide can be found at http://openmx.psyc.virginia.edu/documentation.

See Also

See MxFitFunctionGREML for the S4 class created by mxFitFunctionGREML(). For more information generally concerning GREML analyses, including a complete example, see mxExpectationGREML(). More information about the OpenMx package may be found here.

Examples

gff <- mxFitFunctionGREML()
str(gff)