The mechanism for enforcing those specifications is by adding them to the disclosure file. All of the analysis programs check to see if there is a file named 'disclosure.txt' in the STUDYINF subdirectory of the main SDA dataset. If they find such a file, they enforce the disclosure specifications contained in that file. They also enforce any precision specifications that have been added to that file. Currently only the TABLES and MEANS programs can enforce specified levels of precision.
When a statistic is suppressed, the rest of the table is not affected. Furthermore, summary statistics based on the suppressed statistic(s) are still generated and displayed.
The valid keywords are as follows (all are optional):
Keyword Meaning _____________________________________________________________________ TABLES PROGRAM TABLES= tail(a) ratio(b) efn(c) mincelln(d) mincellwn(e) min(f) minwt(g) Suppress the percentage in a cell if the following specifications are not met. Note that 'p' is the estimated cell percent converted to a proportion. tail: a: P must be greater than or equal to a and less than (1-a) ratio: b: The ratio of two quantities must be less than or equal to b, where EITHER (when p is less than or equal to .5) the numerator of the ratio is the standard error of p divided by p; and the denominator is the negative of the natural logarithm of p, formula: se(p)/p / -ln(p) <= b OR (when p is greater than .5) the numerator of the ratio is the standard error of p divided by (1 minus p), and the denominator is the negative of the natural logarithm of the quantity (1 minus p). formula: se(p)/(1-p) / -ln(1-p) <= b efn: c: Minimum EFFECTIVE number of cases (n/deff) in the DENOMINATOR of the percentage. mincelln: d: Minimum n of cases in the cell (NUMERATOR of the percent) mincellwn: e: Minimum weighted n of cases in the cell (NUMERATOR) min: f: Minimum n of cases in the DENOMINATOR of the percent minwt: g: Minimum weighted n of cases in the DENOMINATOR of the percent MEANS PROGRAM MEANS= min(a) minwt(b) ratio(c) efn(d) Suppress the mean in a cell if the following specifications are not met. min: a: Minimum n of cases in the DENOMINATOR of the mean minwt: b: Minimum weighted n of cases in the DENOMINATOR of the mean ratio: c: Minimum ratio of (mean / SE) efn: d: Minimum effective number of cases (n/deff) in the DENOMINATOR of the mean
The default message, following the keyword that would be used in an internationalization file, is as follows.
DIS_LOWPRECISION = The calculated statistic has very low precision and is not reported.
# PRECISION SPECIFICATIONS ADDEDED TO THE 'disclosure.txt' FILE # Precision specification for precents produced by the TABLES program TABLES= tail(.00005) ratio(.175) efn(68), mincelln(5) mincellwn(.5) min(100) minwt(10) # Precision specifications for means produced by the MEANS program MEANS= min(10) minwt(10) ratio(2) efn(8)
The words "very low precision" are set up to link to a file that could explain further the precision rules and the reasons for setting them up.
# Alternate error message for low precision, with link to a file DIS_LOWPRECISION = The calculated statistic has very low precision and is not reported.
|internationalization||Modifying the SDA user interface language files|