[an error occurred while processing this directive] CENVAR is a screen-oriented, menu-driven software package for the calculation of reliability measures for sample designs ranging from simple random samples of elements to more complex stratified, multistage cluster designs. It is intended for use by statisticians, analysts, and other data users.
CENVAR is the variance calculation component of the Integrated Microcomputer Processing System (IMPS), a series of software packages for entry, editing, tabulation, estimation, analysis, and dissemination of census and survey data. IMPS was developed by the U.S. Bureau of the Census. Distribution of IMPS is funded jointly by the Bureau of the Census and the U.S. Agency for International Development (USAID). CENVAR is based on the PC CARP (Cluster Analysis and Regression Package) software originally developed by Iowa State University.
CENVAR calculates estimates and reliability measures for population parameters such as totals, means, ratios, and proportions, in different domains of estimation. For each specified parameter and domain of estimation, CENVAR produces a tabulated output with the following measures:
CENVAR is completely menu-driven and therefore does not require learning a special programming language. The analysis specification is user-friendly and a number of analyses may be specified to be executed all at once. The specifications may be saved and reused later. CENVAR also allows interaction with DOS.
You specify the sample design variables (stratum, etc.) as applicable. Then you specify the type of analysis, depending on the domain of estimation (the whole universe or a restricted sub-population) and the type of parameter desired (total, ratio, etc.). You also specify the classification variables (to define subpopulations) and the analysis variables (for tabulation).
The output report is in tabular form, and you may select formats for output statistics, for example, points as thousands, separators, and decimal commas. The tabular results are displayed on the screen and can be printed if desired. The output tables are also exportable to spreadsheet software.
To use CENVAR, a description of the file to be processed must be given. To create this description, you use the Data Dictionary component of IMPS, which is provided with CENVAR. The Data Dictionary lets you give a name to each data item in the file, specify its location within a data record, and define the values it may have. These values are used by CENVAR to report statistical measures.
The speed of CENVAR depends on the number of analyses being performed, the number of classification variables and how many categories they have, the number of analysis variables, the size and organization of the data file, and the type of microcomputer being used. On an 80386 microcomputer running at 20 MHz with a math coprocessor, CENVAR completes an analysis for 1 classification variable with 7 categories and 10 analysis variables at a rate of 1 minute for 4,400 records, approximately. Without a math coprocessor, the same analysis takes about 10 minutes.
Hardware and Software
