Multi-dimensional unfolding is a procedure to recover positions of two sets of points from a matrix of distances between the points of both groups. For some of my research work, I implemented the algorithm for metric multi-dimensional unfolding that Peter Schönemann published back in 1970 in Psychometrika. This is not the most advanced algorithm, however it is quite robust and quick when a large number of points is involved. Note that it is an algorithm for metric unfolding. That is, the input data need to be interpretable as real distances.
The package that contains my implementation of Schönemann's algorithm is called munfold. It is now published on CRAN. A windows zip-file can be found here.
Here's the output of a demo run:
Updates of munfold and mclogit
Posted on Wed, 7 Apr 2010 21:28:34 +0100
I just uploaded updates of my packages munfold and mclogit onto my website. The updates have now a more complete documentation so that they pass R CMD check. These updates have also been uploaded to CRAN where I hope they will soon be made publicly available.
R software uploads
Posted on Thu, 18 Feb 2010 22:20:02 +0000
Just finished the pages for some of my R packages (there's more to come). Packages memisc, munfold, and mcogit can now be found on my website.