- Stratified simple random sampling without replacement.
- Stratified two-stage simple random sampling without replacement.
- Stratified multi-stage sampling with replacement in first stage.

Bascula computes adjustment weights using auxiliary variables. It incorporates various weighting techniques. If only categorical auxiliary variables are used, the simplest technique is complete poststratification. For incomplete poststratification, Bascula offers a choice between linear weighting (based on the general regression estimator) and multiplicative weighting (based on iterative proportional fitting). Linear weighting can also be applied if one or more of the auxiliary variables is a quantitative variable.

The program can calculate estimates of population totals, means, and ratios.

Bascula is menu-driven. The order of the menus and of the options within each menu more or less reflects the order in which the various tasks must be carried out.

Bascula is licensed as part of the Blaise system, so it must be kept in mind that the following illustrative prices are essentially Blaise prices and reflect the typical use of this system by large survey groups with many intensive users (interviewers). The price for an annual license is 2000 Dutch guilders per copy, with quantity discounts. The Bascula reference manual includes an introduction to the theory of adjustment weighting, usage instructions, and weighting examples.

In the United States, the base Blaise system costs $2100 for the first developer (no charge for other users, e.g. interviewers and data entry staff) and other modules (including Bascula, which does not require the base system) cost $1200 for the first developer. (Note: prices subject to change, please check with vendor.)

`blaise@cbs.nl`

telephone 0031-70-3374999

Statistics Netherlands, Statistical Informatics Department

P.O. Box 4000, 2270 JM Voorburg, The Netherlands.

**For sales/distribution (U.S.A.):**
Mark Pierzchala, Manager, Blaise Services

telephone (301)315-5959

Westat, Inc.

1650 Research Blvd, Rockville, MD 20850

`blaise@westat.com`

Web site: ```
http://www.westat.com/blaise/
```

**For methodology issues:** N.J. Nieuwenbroek,
`nnwk@cbs.nl`

telephone 0031-45-5706992

Statistics Netherlands,
Department of Statistical Methods

P.O. Box 4481, 6401 CZ Heerlen, The Netherlands.

Web: for more on Bascula:
`http://www.cbs.nl/en/service/blaise/bascula.htm`

Web: for information on Blaise:
`http://www.cbs.nl/en/service/blaise/introduction.htm`

Web: Information on Blaise and Bascula from Westat:
`http://www.westat.com/blaise/`

Variance estimation methods have been added and extended in recent releases, augmenting the original version which was designed only for tabulation and weighting without variance estimation.

Bascula is part of the Blaise project. Blaise is an integrated system for survey processing, focusing on data entry/editing, (telephone) interviewing, electronic data capture, management of surveys, manipulation of data and metadata. The system uses a powerful structured language for describing complex, large, questionnaires. A tabulation utility is part of the system. Links to statistical packages like SPSS and SAS are available. Links to other systems can easily be created.

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