similar to: Visualising the effects of PCAs

Displaying 20 results from an estimated 10000 matches similar to: "Visualising the effects of PCAs"

2017 Jun 13
0
S-mode PCAs
Hi all, I have a file of average SWE observations for 40 years at over 4,000 points and am attempting to do a spatiotemporal analysis of the data using PCA, much like this paper did using snow depth: http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%281998%29011%3C0856%3ATCIRWS%3E2.0.CO%3B2 I have followed the code in the link below by my loadings are far too small (For example, the paper
2012 Oct 26
2
Interpreting and visualising lme results
Dear R users, I have used the following function (in blue) aiming to find the linear regression between MOE and XLA and nesting my data by Species. I have obtained the following results (in green). model4<-lme(MOE~XLA, random = ~ XLA|Species, method="ML")summary(model4) Linear mixed-effects model fit by maximum likelihood Data: NULL         AIC     BIC   logLik  -1.040187 8.78533
2002 Dec 09
2
Principal component analysis
Dear R users, I'm trying to cluster 30 gene chips using principal component analysis in package mva.prcomp. Each chip is a point with 1,000 dimensions. PCA is probably just one of several methods to cluster the 30 chips. However, I don't know how to run prcomp, and I don't know how to interpret it's output. If there are 30 data points in 1,000 dimensions each, do I have to
2008 Jun 05
3
How to combine to PCAs
Dear all: Subjects were measured two times (t1 and t2) on different variables (v1 ... vn). Between t1 and t2 there was an experimental manipulation. I computed two PCAs for time-points t1 and t2. Is it possible to combine both PCAs in order to get only one set of eigenvectors? Due to the experimental manipulation measurement values on time points t1 and t2 changed for each subject. Many
2009 Nov 04
2
PCA with tow response variables
Hi all, I'm new to PCA in R, so this might be a basical thing, but I cannot find anything on the net about it. I need to make a PCA plot with two response variables (df$resp1 and df$resp2) against eight metabolites (df$met1, df$met2, ...) and I don't have a clue how to do... and I've only used the simplest PCAs before, like this: pcaObj=prcomp(t(df[idx, c(40:47)]))
2012 Mar 13
1
Visualising multiple response contingency tables
Dear R Help Community, I have a question and an answer (based on reading this forum and online research), but I though I should share both since probably there's a much better way to go about my solution. My question is specifically about how to best visualise multiple response contingency tables. What I mean by 'multiple response' is that the total number of responses per row of a
2006 Apr 20
2
PCA biplot question
Hi everyone, I'd like to project two pcas onto one device window. I plot my first PCA: biplot(prcomp(t(cerebdevmat)), var.axes=FALSE, cex=c(1,.1), pc.biplot=TRUE) Now I'd like to project the features of another PCA onto this graph. Any suggestions? I know this is easily done in MatLab but haven't figured it out in R. Thanks, Tanya [[alternative HTML version deleted]]
2000 Apr 26
1
Factor Rotation
How does one rotate the loadings from a principal component analysis? Help on function prcomp() from package mva mentions rotation: Arguments retx a logical value indicating whether the rotated variables should be returned. Values rotation the matrix of variable loadings (i.e., a matrix whose olumns contain the eigenvectors). The function princomp returns this in the element
2003 Oct 28
2
Visualising Moving Vectors
I am wanting to plot a series of wind vectors onto a contoured area map for a series of weather stations (eg arrows showing wind speed/direction for a particular time snapshot), can someone please advise me how best to approach this? My desired end point is to be able to link a time series of such data together so that I will in effect have a "movie" displaying the evolution of these
2003 Nov 03
1
Visualising Vectors
I sent a mail last week asking for some advise in relation to displaying wind vectors on a contour map of a region. Whilst I have had some useful feedback relating to the second part of this question (namely how to animate a time series of still frames), I haven't recieved any advise on how I might create the still images of the spatially distributed wind vector data at any given time point.
1998 Aug 26
0
prcomp & princomp - revised
My previous post about prcomp and princomp was done in some haste as I had long ago indicated to Kurt that I would try to have this ready for the June release, and it appeared that I would miss yet another release. I also need to get it out before it becomes hopelessly buried by other work. Brian Ripley kindly pointed out some errors, and also pointed out that I was suggesting replacing some
2010 Dec 14
0
googleVis 0.2.2 - Using the Google Visualisation API with R
Hi all, Version 0.2.2 of the googVis package has been released on CRAN and will be available from your local CRAN mirror in due course. googleVis provides an interface between R and the Google Visualisation API. The functions of the package allow users to visualise data stored in R with the Google Visualisation API without uploading their data to Google. We presented our initial ideas on
2010 Dec 14
0
googleVis 0.2.2 - Using the Google Visualisation API with R
Hi all, Version 0.2.2 of the googVis package has been released on CRAN and will be available from your local CRAN mirror in due course. googleVis provides an interface between R and the Google Visualisation API. The functions of the package allow users to visualise data stored in R with the Google Visualisation API without uploading their data to Google. We presented our initial ideas on
2011 Feb 08
0
Update: googleVis 0.2.4 - Using the Google Visualisation API with R
Hi all, Version 0.2.4 of the googVis package has been released on CRAN and will be available from your local CRAN mirror soon. googleVis provides an interface between R and the Google Visualisation API. The functions of the package allow users to visualise data stored in R with the Google Visualisation API without uploading their data to Google Since the last version a lot of work has been
2011 Feb 08
0
Update: googleVis 0.2.4 - Using the Google Visualisation API with R
Hi all, Version 0.2.4 of the googVis package has been released on CRAN and will be available from your local CRAN mirror soon. googleVis provides an interface between R and the Google Visualisation API. The functions of the package allow users to visualise data stored in R with the Google Visualisation API without uploading their data to Google Since the last version a lot of work has been
2012 Jun 21
0
prcomp
Hi, If center=T (by default) in invoking prcomp, that is, prcomp (x) where x is a matrix with the observations are in rows and the variables are in column, is this equivalent to scale(t(x),center=T,scale=F)?where?x is a matrix with?the observations are in rows and the variables are in columns? Additionally, could you advise when the variables should mean centered (center = T in prcomp) before the
2016 Mar 24
0
summary( prcomp(*, tol = .) ) -- and 'rank.'
Martin, I fully agree. This becomes an issue when you have big matrices. (Note that there are awesome methods for actually only computing a small number of PCs (unlike your code which uses svn which gets all of them); these are available in various CRAN packages). Best, Kasper On Thu, Mar 24, 2016 at 1:09 PM, Martin Maechler <maechler at stat.math.ethz.ch > wrote: > Following from
2010 Jul 19
0
[LLVMdev] How to visualise Clang optimisation phases
Having a look at clang's source, you can find in "lib/CodeGen/BackendUtil.cpp" the functions where clang builds the passes to emit code. The optimization passes used are there and you can simulate them via the "opt" utility, by running each pass one at a time. LLVM also declares standard module/function passes on include/llvm/Support/StandardPasses.h. Have a look and see
2004 Mar 17
0
mva :: prcomp
Dear R-list users, I'm new to principal components and factor analysis. I thought this method can be very useful for me to find relationships between several variables (which I know there is, only don't know which variables exactly and what kind of relation), so as a structure detection method. Now, I'm experimenting with the function prcomp from the mva package. In my source code
2011 Oct 23
1
how to plot a distribution of mean and standard deviation
Hi, I have the following data about courses (504) in a university, two attributes about the proportion of resources used (#resources_used / #resources_available), namely the average and the standard deviation. Thus I have: [1] n=504 rows [2] 1 id column and 2 attributes Here's a sample of the data: courseid,average,std 12741,1,0 17161,1,0 12514,1,0