Zelig is statistical software for everyone: researchers, instructors, and students. It is a front-end and back-end for R (Zelig is written in R). The Zellig software:
- Unifies diverse theories of inference
- Unifies different statistical models and notation
- Unifies R packages in a common syntax
Zelig is distributed under the GNU General Public License, Version 2. After installation, the source code is located in your R library directory. You can download a tarball of the latest Zelig source code from http://gking.harvard.edu/src/contrib/.
The Dataverse Network software uses Zelig to perform advanced statistical analysis functions. The current interface schema used by the DVN for Zelig processes is in the following location:
http://thedata.org/files/thedata/schema/ZeligInterfaceDefinition_1_1.xsd
Three factors determine which Zelig models are available for analysis in the DVN:
- Some new models require data structures and modeling parameters that are not compatible with the current framework of the DVN and other web-driven applications. These types of models are not available in the DVN.
- Models must be explicitly listed in the Zelig packages to be used in the DVN, and all models must be disclosed fully, including runtime errors. Zelig models that do not meet these specifications are excluded from the DVN until they are disclosed with a complete set of information.
- An installation-based factor also can limit the Zelig models available in the DVN. A minimum version of the core software package GCC 4.0 must be installed on any Linux OS-based R machine used with the DVN, to install and run a key Zelig package, MCMCpack. If a Linux machine that is designated to R is used for DSB services and does not have the minimum version of the GCC package installed, the DVN looses at least eight models from the available advanced analysis models.