L.S. We would like to generate fractional design for a conjoint analysis. For example we would like to reduce 2x2x2x2x3 --> 12-16 profiles. We tried the R-package "conjoint" and we found an article which describes how to make fractional design for these kinds of studies with Algdesign:
http://tolstoy.newcastle.edu.au/R/e10/help/att-8876/DCE_with_R.pdf However, the generated fractional design can be quite unbalanced in the number of levels for each attribute, probably because the fractional design is constructed as orthogonal as possible. For estimating the main effects we would prefer optimal designs in which the number of levels in each attribute is as equal as possible. Anyone has an idea how to construct such designs with R? Thanks in advance! Eric Boer Food and Biobased Research Wageningen UR The Netherlands [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
