Multivariate Transformations
On Wed, 2009-05-27 at 08:39 -0400, stephen sefick wrote:
It depends on what you are after. I am by no means a wunderkind when it comes to transformation, but in the package vegan type ?wisconsin and that should give you a start, but if you know what transformations you would like to preform then apply should do what you need with whatever transformation you are trying to use.
decostand provides (mostly) standardisations not transformations, it even says so. What Holger is looking for is something like a Box Cox transform for bivariate normality but to instead achieve multivariate normality. That is a different kettle of fish to what decostand tries to do. HTH G
Stephen Sefick On Wed, May 27, 2009 at 5:26 AM, Hollix <Holger.steinmetz at web.de> wrote:
Hello folks, many multivariate anayses (e.g., structural equation modeling) require multivariate normal distributions. Real data, however, most often significantly depart from the multinormal distribution. Some researchers (e.g., Yuan et al., 2000) have proposed a multivariate transformation of the variables. Can you tell me, if and how such a transformation can be handeled in R? Thanks in advance. With best regards Holger --------------- Yuan, K.-H., Chan, W., & Bentler, P. M. (2000). Robust transformation with applications to structural equation modeling. British Journal of Mathematical and Statistical Psychology, 53, 31?50. -- View this message in context: http://www.nabble.com/Multivariate-Transformations-tp23739013p23739013.html Sent from the R help mailing list archive at Nabble.com.
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