help agrm
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Title

    agrm -- Calculate measure of agreement "A".


Syntax

    [by:varlist] agrm varlist [if] [in] [weight] [, generate(newvar)
    categories(integer) bounds(numlist) missing(numlist) detail noprint]


Description

    agrm calculates Cees van der Eijk's (2001) alternative measure of
    agreement "A".  This measure is a weighted average of the degree of
    agreement among respondents that exists in the simple component parts –
    layers – into which any frequency distribution can be disaggregated.  It
    is especially useful when calculating agreement in ordered rating scales
    and easily interpretable, ranging from -1 (perfect bimodality) to +1
    (perfect unimodality).


Options

    generate(newvar) creates a new variable newvar which returns the
    according value of "A".

    categories(integer) specifies the number of total categories.  It allows
    to calculate the measure of agreement regardless of empty categories.

    bounds(numlist) customizes the lower and upper bounds of the measure of
    agreement.

    missing(numlist) specifies the numeric values of missing values.

    detail displays additional statistics.

    noprint suppresses the output.


Remarks

    The measure of agreement is highly sensitve to the number of categories
    of the ordered rating scale.  In order to mitigate the risk of
    miscounting the number of categories the agrm command takes advantage of
    all the information provided in the data set (e.g. value labels).  The
    output window reports the number of categories used to calculate the
    measure of agreement.  Please double-check with the actual length of the
    ordered rating scale.  If necessary, use the categories(integer) option
    to manually adjust the number of categories.

    Please note that the agrm command is unable to handle both negative
    category values and noninteger category values.  If you encounter such
    data in your data set, use the recode command to obtain an ordered rating
    scale with positive and integer category values.

    For more detailed informtion on the measure of agreement, see van der
    Eijk (2001).


Examples

    . bysort country: agrm socsec

    . agrm tax environment, generate(agreement)

    . agrm socsec, categories(5)

    . agrm tax, bounds(0 1) missing(99) detail


Saved results

    agrm saves the following in r():

      r(mean)     mean
      r(min)      minimum
      r(max)      maximum
      r(sd)       standard deviation
      r(A)        measure of agreement "A"

Refereces

    van der Eijk, Cees. 2001. "Measuring Agreement in Ordered Rating Scales."
    Quality and Quantity 35 (3): 325-341.


Author

    A. Ecker, Department of Government, University of Vienna. Please email to
    alejandro.ecker@univie.ac.at if you observe any problems.