As the literature on matching techniques is rapidly evolving, MATCHIT will strive to incorporate new developments. MATCHIT is thereby an evolving program. Users may be concerned that analysis written in a particular version may not be compatible with newer versions of the program. The primary way to ensure that replication archives remain valid is to record the version of MATCHIT that was used in the analysis. Our website maintains binaries of all public release versions, so that researchers can replicate results exactly with the appropriate version (for Unix-based platforms, see http://gking.harvard.edu/src/contrib/; for windows, see http://gking.harvard.edu/bin/windows/contrib/).
In addition, users may find it helpful to install packages with version control, using the installWithVers command with install.packages. So for example, in the windows R console, users may download the appropriate version from our website and install the package with version control by:
install.packages(choose.files('',filters=Filters[c('zip','All'),]),
.libPaths()[1],installWithVers=T,CRAN=NULL)
R CMD INSTALL similarly permits users to specify this version
using the
-with-package-versions option. After having
specified version control, different versions of the program may be
called as necessary. Similar advice may also be appropriate for
version control for R more generally.