help sratio
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Title

    sratio -- Displays a table of ratio study statistics, particularly for
                evaluating mass appraisal performance
    
Syntax

        sratio varlist [if] [in] [, options]

    options             Description
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    Options
      sample            displays general information about the sample
      assess            displays measures of appraisal level
      reliable          displays measures of reliability
      uniform           displays primary measures of appraisal uniformity
      disperse          displays detailed measures of dispersion
      coc               displays measures of concentration
      brief             displays measures of assessment, primary measures of
                          uniformity, and measures of reliability
      detail            displays in detail all measures of appraisal level
                          and uniformity; by default if no other option is
                          specified.
      level(#)          sets confidence level(in percent); default is
                          level(95) or as set by set level; see level
      ioc(#)            sets the low and upper limit of the desired
                          concentration interval; default is ioc (0.90 1.10)
      pioc(#)           sets the desired concentration level in term of
                          percentages (values between 0 and 100); default is
                          pioc (10)
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    by may be used with sratio; see by.

Description

    sratio calculates and displays a variety of ratio study statistics in a
    single table. These include measures of appraisal level, appraisal
    uniformity (dispersion and concentration), and reliability.

    With the by option, sratio allows you to display the output by categories
    of a grouping variable.

    With the different options available, sratio allows more flexibility in
    terms of the measures of performance presented.

    sratio takes, as input, a list of two scale variables that have positive
    values.sratio implicitly computes the ratio of these two variables by
    dividing the first variable (the numerator) by the second variable
    (denominator) on the list provided (varlist). In appraisal ratio studies,
    the numerator could be the appraisal or assessment value and the
    denominator could be the market value.

Examples

. sratio  AppraisedValue SalePrice 
. by  Strata, sort : sratio  AppraisedValue SalePrice
. sratio  AppraisedValue SalePrice, brief
. sratio  AppraisedValue SalePrice, assess
. sratio  AppraisedValue SalePrice, level(90) ioc(0.80 1.10) pioc(10 20 30 35) 

Author 

    Benmamoun, Mamoun, Public Policy Research Center, University of Missouri
    – St. Louis , Saint Louis, MO, U.S.A.  Email  vmamoun@yahoo.com if you
    observe any problem or if you have any comment or question.

Remarks 
 
    For detailed information on ratio statistics for mass appraisal, see
    "International Association of Assessing Officers. 1999. Standard on ratio
    studies. Chicago: International Association of Assessing Officers."

Acknowledgement 

    I would like to acknowledge Steve Gardner of the Public Policy Research
    Center at the University of Missouri – St. Louis for his mentorship and
    training in this area of research.

Also see

    Online:  summarize, tabstat, ci , centile, tcod