vcms, vcxs
==============================================
Purpose
----------------
Computes the observed variance-covariance matrix.
.. NOTE:: :func:`vcms` and :func:`vcxs` have been replaced with functions :func:`varCovX` and :func:`varCovM`
whose descriptions use more standard statistical nomenclature. :func:`vcxs` and :func:`vcms` will continue
to be available for backwards compatibility.
Format
----------------
.. function:: vc = vcms(m)
vc = vcxs(x)
:param m: A constant term MUST have been the first variable when the moment matrix was computed.
:type m: KxK moment (:math:`x'x`) matrix
:param x: data
:type x: NxK matrix
:return vc: the observed-covariance matrix of *m* or *x*.
:rtype vc: KxK matrix
Remarks
-------
The variance covariance matrix is that of the input data matrix. It is
computed as the moment matrix of deviations about the mean divided by
the number of observations :math:`N`. For an unbiased estimator covariance
matrix which uses :math:`N - 1` rather than :math:`N` see :func:`vcm` or :func:`vcx`.
Source
------
corrs.src
.. seealso:: Functions :func:`momentd`, :func:`corrms`