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help for variancemat
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Generate a matrix of variances

        variancemat varlist [if exp] [in range] [weight], matname(matrix)
                 [common]


Description

    variancemat generates an n by 1 matrix of the variances of the variables
    in varlist.

    The rownames of matrix will be the variable names in varlist; the colname
    of column 1 will be "variance".

    aweights, iweights, and fweights are allowed; aweight is the default.


Required Options

    matname(matrix) specifies the name of the matrix to be created.  If
    matrix already exists as a scalar or matrix, it will be overwritten.

Optional Options

    common specifies that the variances are to be calculated on the common
    set of observations that are nonmissing for all variables in varlist.
    The default is for variances to be calculated for each variable
    independently. In either case, the variance calculations are additionally
    restricted by any [if exp] or [in range] conditions that may be present.


Examples

    . variancemat age income numkids, matname(m)

    . variancemat age income numkids, matname(m) common

    . variancemat age income numkids if numkids>0, matname(m)

    . variancemat age income numkids [aw= wgt1], matname(m)


Remarks

    variancemat was written for use by an earlier version of mahapick, but
    has been superseded by covariancemat in that application.  It may be of
    use in other circumstances.


Author
    David Kantor; initial development was done at The Institute for Policy
    Studies, Johns Hopkins University.  Email kantor.d@att.net if you observe
    any problems.

Also See
    covariancemat, mahapick, mahascore, mahascores, mahascore2,