Hello, I am trying to track down the email address of Igor - I am interested in his response (Re: canonical correlation analysis) and would like to ask further questions, Regards, Meegan
[EMAIL PROTECTED] wrote: > I haven't seen the question, but judging by the below respond, under > consideration is estimation of overall variance of all morphological > characters explaned by all environmental characters. If it is the case, > and if characters are multinormally ditsibuted, then canonical analysis > would work instead of PCA. > Igor > > ----- Original Message ----- > From: <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Tuesday, September 14, 2004 3:55 PM > Subject: Re: canonical correlation analysis > > > Meeghan, > > > > As far as I can understand your problem you may not be able to compute > > an overall percent of morphology ( which is not one variable, but > > several) explained by your 5 environmental variables. What you > > definitely can compute would be a single percentage (r^2) of each > > morphological variable explained by the five environmental variables. > > > > By doing PCA on the morphological variables you might find one major > > PCA that has a sizable percentage of its variability explained by the > 5 > > environmental variables. Another might also have much of its > > variability explained. Adding them together might equal greater than > > 100%. By looking at total variability via summing the PC or looking > > at them individually you can perhaps understand why the fractions > > explained of each can not be added together in any way to give an > > overall % explained. It would be like adding apples and oranges. > > > > Joe Kunkel > > > > On Sep 8, 2004, at 9:31 AM, [EMAIL PROTECTED] wrote: > > > > > Hello, > > > I am a PhD student at the University of Adelaide. I am working on > > > morphological data of a common species of marine kelp that I > collected > > > across Southern Australia (i.e. height, weight, surface area etc). I > > > also have 5 environmental variables (latitude, longitude, exposure, > > > depth and plant density) and I am wanting to do a canonical > > correlation > > > analysis (CCA) to examine the overall ability of the suite of > recorded > > > environmental variables to explain the variation in morphological > > > characters. > > > > > > I have attempted a CCA in numerous programs (Statistica, SYSTAT and > > > PC-ORD) but can not get all the information that I require from > these > > > programs (see query below). Whilst I would like to try the analysis > on > > > SPSS, this needs to be done on the MANOVA subprogram of SPSS. > Firstly, > > > is there anyone familiar with this program is it part of SPSS or do > I > > > need to access this as a separate program? > > > > > > Using the 3 programs mentioned above, I have been able to calculate > > the > > > correlation coefficients for the morphological and environmental > > > variables and yet can not calculate the variance explained (%) by > each > > > canonical axis (i.e. the proportion of the pattern common to the two > > > data sets represented by each canonical axis). > > > Secondly, whilst I can obtain the correlations between canonical > > > axes and morphological and environmental variables (i.e. canonical > > > factor loadings) as well as the variance explained by each axis (for > > > both the Morphological and Environmental data sets), I can not > > > calculate > > > the cumulative variance of morphological characters explained by > > > canonical variates of environmental variables (%) (i.e. what the % > of > > > the variation in the morphometric data set do the 5 environmental > > > variables (collectively) explain). Both of these outputs are the > main > > > results I am after and I am unable to obtain them. Any advice on how > > to > > > calculate these results or programs that include these results in > the > > > CCA output would be greatly appreciated! > > > > > > Kind Regards, > > > Meegan > > > > > > _____________________________________ > > > > > > Meegan Fowler-Walker > > > PhD student > > > Southern Seas Ecology Laboratories > > > School of Earth and Environmental Sciences > > > University of Adelaide > > > South Australia 5005 > > > Australia > > > > > > Phone: +61 8 8303 6224 > > > Fax: +61 8 8303 4364 > > > Email: [EMAIL PROTECTED] > > > == > > > Replies will be sent to list. > > > For more information see > > > http://life.bio.sunysb.edu/morph/morphmet.html. > > > > > > > > ---------------------------------------------------- > > Joseph G. Kunkel, Professor > > Biology Department > > University of Massachusetts Amherst > > Amherst, MA 01003 > > http://www.bio.umass.edu/biology/kunkel/ > > == > > Replies will be sent to list. > > For more information see > http://life.bio.sunysb.edu/morph/morphmet.html. > == > Replies will be sent to list. > For more information see http://life.bio.sunysb.edu/morph/morphmet.html. == Replies will be sent to list. For more information see http://life.bio.sunysb.edu/morph/morphmet.html.
