help parttau
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Title

    parttau -- Calculate Kendall's partial tau and confidence interval.


Syntax
        parttau varlist [if] [in] [, options]

    When varlist contains three or more variables, the first two are the
    primary variables, and all others confounders.  When varlist contains two
    variables, the pairwise tau is calculated.

    options               Description
    -------------------------------------------------------------------------
    Main
      cluster(varname)    treat data set as samples of clusters
      wcluster            calculate the within-cluster partial and pairwise
                            taus
      estimate(varname)   save jackknife estimates in given variable name
      transform(string)   report the tau, SE, and confidence interval in a
                            transformed space; transformations are same as
                            for somersd; see below
      level(#)            specifies percent coverage for confidence interval
      run2                forces calculation of pairwise tau when no
                            confounder is given; see below
      show                displays all pairwise taus between all given
                            variables
    -------------------------------------------------------------------------


Options
        +------+
    ----+ Main +-------------------------------------------------------------

    cluster(varname) instructs the program that the data set should be
        treated as samples of clusters from a population of clusters, and
        that the given variable specifies the clusters.  If cluster is
        specified and the option wcluster is not specified, then the partial
        tau is calculated between clusters.

    estimate(varname) specifies that the jackknife estimates should be saved
        in variable varname.  If the variable exists prior to calling this
        option, the variable is overwritten and a warning message given.
        Otherwise a variable with the given name is created.

    transform(name) changes the ouput estimate, SE, and confidence interval
        to a transformed space. If specified, the confidence interval will be
        symmetric in the transformed space.  Allowed transformations are same
        as for somersd:  z, asin, rho, zrho, c, though fewer aliases are
        allowed.  If calculating a partial tau (i.e., using one or more
        confounder variables), and option show is specified, reported
        pairwise taus will not be transformed.

    level(#) specifies the percent coverage of the confidence interval.

    run2 forces calculation of pairwise tau.  parttau is primarily intended
        for calculating Kendall's partial tau between two variables with one
        or more confounders.  Thus, typically, three or more variables will
        be specified.  If two variables are specified, parttau will assume
        that the user wants to calculate the pairwise tau and will attempt to
        use somersd.  If that program is not found, parttau will calculate
        the pairwise tau itself.  Using run2 forces parttau to calculate the
        pairwise tau; if somersd is installed, both will be used.

    show displays all pairwise taus between all given variables.  The
        pairwise taus are also saved in the matrix e(taus).

Description

    parttau calculates Kendall's partial tau and confidence interval.
    parttau can be used to calculate pairwise taus if somersd is not
    installed, or if the option run2 is specified.  For repeated calculation
    of the pairwise tau, the user will probably find somersd preferable; it
    is faster and has more options.

Authors

    James Fiedler, Universities Space Research Association
    Email: james.fiedler-1@nasa.gov

    Alan H. Feiveson, National Aeronautics and Space Administration