Title
tcod -- Displays standard and bootstrap confidence intervals for the coefficient of dispersion (COD) & performs Gloudemans’ COD Tolerance Tests.
Syntax
tcod varname [if] [in] [, options]
options Description ------------------------------------------------------------------------- Options level(#) sets confidence level (in percent). The default is level(95) or as set by set level; see level stdr(#) sets the values of the required standards. The default is stdr (15) reps(#) specifies the number of bootstrap replications to be performed; the default is reps (50). The bootstrapped confidence interval reported is the BCa confidence interval. ------------------------------------------------------------------------- by may be used with tcod; see by.
Description
tcod computes the confidence intervals for the COD, the maximum acceptable COD, and tests the hypothesis that the COD meet the performance standards for the uniformity of assessments.
With the by option, tcod allows you to display the output by categories of a grouping variable.
tcod takes, as input, one scale variable. In appraisal ratio studies, this variable could be the appraisal or assessment ratio.
Examples
. tcod Ratio . by Strata, sort : tcod Ratio . tcod Ratio, stdr(15 20 25) reps(5000)
Author
Benmamoun, Mamoun, Boeing Institute of International Business, Saint Louis University , 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 , see Gloudemans, R. J. 2001. Confidence Intervals for the COD: Limitations and Solutions. Available online at http://www.agjd.com/COD.pdf.
Acknowledgement
This program is based on the distingusihed work of Gloudemans, Robert J.
Also see
Online: bootstrap, sratio, codci