Can R do a repeated measures MANOVA and tell what dimensionality the statistical variance occupies? I have been using MATLAB and SPSS to do my statistics. MATLAB can do ANOVAs and MANOVAs. When it performs a MANOVA, it returns a parameter d that estimates the dimensionality in which the means lie. It also returns a vector of p-values, where each p_n tests the null hypothesis that the mean vectors lie in an n-1 dimensional space (0-D space implies same vector, 1-D space implies scaled vectors that point in the same direction, etc...). However, MATLAB does not do repeated measures MANOVA. SPSS can do repeated measures MANOVA but it does not return this dimension output. Hence, I'm trying to find an environment that will allow me to do repeated measures MANOVA and determine the dimensionality of the space, before I spend several weeks trying to learn it. I know the dimensionality parameter is based upon the eigenvalues of the ratio of the different SSCP (sum of squares and cross products) matrices, but a) I'm not sure how to calculate the SSCP matrices for repeated measures MANOVA, and b) once I get these eigenvalues and convert them a Pillai-Bartlett or Wilk's-Lambda value, I don?t know how to convert to an f-statistic. Does anybody know how to do this or has repeated measures MANOVA in R (while returning the dimensionality parameter)? Thanks in advance for your help. Bolu --
A. Bolu Ajiboye wrote:> Can R do a repeated measures MANOVA and tell what dimensionality the statistical variance occupies? > > I have been using MATLAB and SPSS to do my statistics. MATLAB can do ANOVAs and MANOVAs. When it performs a MANOVA, it returns a > parameter d that estimates the dimensionality in which the means lie. It also returns a vector of p-values, where each p_n tests > the null hypothesis that the mean vectors lie in an n-1 dimensional space (0-D space implies same vector, 1-D space implies scaled > vectors that point in the same direction, etc...). However, MATLAB does not do repeated measures MANOVA. SPSS can do repeated > measures MANOVA but it does not return this dimension output. Hence, I'm trying to find an environment that will allow me to do > repeated measures MANOVA and determine the dimensionality of the space, before I spend several weeks trying to learn it. > > I know the dimensionality parameter is based upon the eigenvalues of the ratio of the different SSCP (sum of squares and cross > products) matrices, but a) I'm not sure how to calculate the SSCP matrices for repeated measures MANOVA, and b) once I get these > eigenvalues and convert them a Pillai-Bartlett or Wilk's-Lambda value, I don?t know how to convert to an f-statistic. > > Does anybody know how to do this or has repeated measures MANOVA in R (while returning the dimensionality parameter)? Thanks in > advance for your help.I don't know about the dimensionality parameter, but have a look at anova.mlm(). In particular, you might want to run example(anova.mlm) and study the output. Also, you might look at SSD() and summary.manova() in package stats.> Bolu > > > > -- > > ______________________________________________ > R-help at stat.math.ethz.ch 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.-- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894
I have an in press paper on HE plots, http://www.math.yorku.ca/SCS/Papers/heplots.pdf that describes methods to visualize the dimensionality of effects in MLMs. The implementation is in SAS, but there's a link to a rudimentary R function in the paper. -Michael A. Bolu Ajiboye wrote:> Can R do a repeated measures MANOVA and tell what dimensionality the statistical variance occupies? > > I have been using MATLAB and SPSS to do my statistics. MATLAB can do ANOVAs and MANOVAs. When it performs a MANOVA, it returns a > parameter d that estimates the dimensionality in which the means lie. It also returns a vector of p-values, where each p_n tests > the null hypothesis that the mean vectors lie in an n-1 dimensional space (0-D space implies same vector, 1-D space implies scaled > vectors that point in the same direction, etc...). However, MATLAB does not do repeated measures MANOVA. SPSS can do repeated > measures MANOVA but it does not return this dimension output. Hence, I'm trying to find an environment that will allow me to do > repeated measures MANOVA and determine the dimensionality of the space, before I spend several weeks trying to learn it. > > I know the dimensionality parameter is based upon the eigenvalues of the ratio of the different SSCP (sum of squares and cross > products) matrices, but a) I'm not sure how to calculate the SSCP matrices for repeated measures MANOVA, and b) once I get these > eigenvalues and convert them a Pillai-Bartlett or Wilk's-Lambda value, I don?t know how to convert to an f-statistic. > > Does anybody know how to do this or has repeated measures MANOVA in R (while returning the dimensionality parameter)? Thanks in > advance for your help. > > Bolu > > > > -- > > ______________________________________________ > R-help at stat.math.ethz.ch 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.-- Michael Friendly Email: friendly AT yorku DOT ca Professor, Psychology Dept. York University Voice: 416 736-5115 x66249 Fax: 416 736-5814 4700 Keele Street http://www.math.yorku.ca/SCS/friendly.html Toronto, ONT M3J 1P3 CANADA