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...203712 [5,] 0.2698180 2.075759 2.869573 > > ### Simualte multivarite gaussin data ( gives Error) > Sigma<-COV(p = 3, sd = 2, r= -0.6) > mu<-1:3 > mvrnorm(5, mu=mu, Sigma=Sigma) Error in mvrnorm(5, mu = mu, Sigma = Sigma) : 'Sigma' is not positive definite -- Mizanur Khondoker Division of Pathway Medicine (DPM) The University of Edinburgh Medical School The Chancellor's Building 49 Little France Crescent Edinburgh EH16 4SB United Kingdom Tel: +44 (0) 131 242 6287 Fax: +44 (0) 131 242 6244 http://www.pathwaymedicine.ed.ac.uk/

...ne. However, I am looking for a solution when this kind of facility is not available on the cluster, for example , by modifying the code so that the job can checkpoint and restart by itself. Does anyone have any experience or idea of doing so? Any help would be greatly appreciated. -- Mizanur Khondoker Division of Pathway Medicine (DPM) The University of Edinburgh Medical School The Chancellor's Building 49 Little France Crescent Edinburgh EH16 4SB United Kingdom Tel: +44 (0) 131 242 6287 Fax: +44 (0) 131 242 6244 http://www.pathwaymedicine.ed.ac.uk/ [[alternative HTML version deleted]]

...r two class problems shows collinearity for p > n-2. Does anyone know why this is the case? Does lda (MASS) use a different algorithm? #Question2: #========= When I plot leave-one-out CV based on lda (averaged over 500 simulated data sets), I see a pick (see the link http://homepages.ed.ac.uk/mkhondok/temp/lda_R-help-CV.png ) at p = n-3 (not n-2!). I would appreciate if someone could help me get an explanation for this behaviour. ## R code ## Reproducible example library(MASS) # n: sample size # p: number of variables ## Function ## -------- test.fun<-function(n,p){ x<-matrix (rnorm(n...