similar to: A point in a vector?

Dear R-friends, How do you test the goodness of prediction of a model, when you predict on a set of data DIFFERENT from the training set? I explain myself: you train your model M (e.g. glm,gam,regression tree, brt) on a set of data A with a response variable Y. You then predict the value of that same response variable Y on a different set of data B (e.g. predict.glm, predict.gam and so on).

I am using nls to fit a non linear function to some data. The non linear function is: y= 1- exp(-(k0+k1*p1+ .... + kn*pn)) I have chosen algorithm "port", with lower boundary is 0 for all of the ki parameters, and I have tried many start values for the parameters ki (including generating them at random). If I fit the non linear function to the same data using an external

Dear friends, what is this error message in gam???? I cannot understand what it means .... is it a bug? gam_bray_scot24_pc_0505<gam(bray~s(PC1,PC2,PC3,PC4,PC5, PC1.1,PC2.1,PC3.1,PC4.1,PC5.1),data=dist_scot24_vector_with_climate) Error in if (length(data) != vl) { : missing value where TRUE/FALSE needed Calls: gam ... smooth.construct -> smooth.construct.tp.smooth.spec -> array In

Dear friends, I am testing glm as at page 514/515 of THE R BOOK by M.Crawley, that is on proportion data. I use glm(y~x1+,family=binomial) y is a proportion in (0,1), and x is a real number. I get the error: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! But that is exactly what was suggested in the book, where there is no mention of a similar warning. Where am I

Dear friends, Do you know how to calculate the CONCAVE hull of a set of points (2- dimensional or n-dimensional)? is that possible in R? (With a "smoothing" parameter of course). Best, -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk

Dear friends, I have to use a very large matrix. Something of the sort of matrix(80000,80000,n) .... where n is something numeric of the sort 0.xxxxxx I have not found a way of doing it. I keep getting the error Error in matrix(nrow = 80000, ncol = 80000, 0.2) : too many elements specified Any suggestions? I have searched the mailing list, but to no avail. Best, -- Corrado Topi Global

Dear R list, I just obtained a negative AIC for two models (-221.7E+4 and -230.2E+4). Is that normal? Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk

Dear R gurus, I have some climatic data for a region of the world. They are monthly averages 1950 -2000 of precipitation (12 months), minimum temperature (12 months), maximum temperature (12 months). I have scaled them to 2 km x 2km cells, and I have around 75,000 cells. I need to feed them into a statistical model as co-variates, to use them to predict a response variable. The climatic

Dear R-experts, I have a question on the formulas used in the gam function of the mgcv package. I am trying to understand the relationships between: y~s(x1)+s(x2)+s(x3)+s(x4) and y~s(x1,x2,x3,x4) Does the latter contain the former? what about the smoothers of all interaction terms? I have (tried to) read the manual pages of gam, formula.gam, smooth.terms, linear.functional.terms but

Dear R-experts, I have a question on the formulas used in the gam function of the mgcv package. I am trying to understand the relationships between: y~s(x1)+s(x2)+s(x3)+s(x4) and y~s(x1,x2,x3,x4) Does the latter contain the former? what about the smoothers of all interaction terms? I have (tried to) read the manual pages of gam, formula.gam, smooth.terms, linear.functional.terms but

Hi List, Does any one know what package I need to use in order to fetch/get a large sized dataframe from SQL? I have already used sqldf package which is good for fetching large sized csv files. Thanks Alireza [[alternative HTML version deleted]]

Hi all, Working with S4 object, I definine two class foo1 and foo2. I define '[' (resp. '[<-') for the two classes. Then I define a third class foo3 that inherit from both foo1 and foo2. Is there a way to make '[' (resp. '[<-') for foo3 inherit from '[' (resp. '[<-') for foo1 and foo2? Thanks Christophe

Quick informal poll: what is everyone's favorite text editor for working with R? I'd like to hear from people who are using editors that have some level of direct R interface (e.g. Tinn-R, Komodo+SciViews). Thanks! --j -- Jonathan A. Greenberg, PhD Postdoctoral Scholar Center for Spatial Technologies and Remote Sensing (CSTARS) University of California, Davis One Shields Avenue The

Hi R users, I try to build a function to compute odds ratio and relative risk however something wrong. I stuck for many hours but I really don't know how to solve it. Would someone please give me a hint? > OR.RR<-function(x){ + x <- as.matrix(any(dim(x)==2)) + OR<-(x[1,1]*x[2,2])/(x[1,2]*x[2,1]) + RR<-(x[1,1]/(sum(x[1,])))/(x[2,1]/(sum(x[2,]))) +

Dear All, The Decision and Policy Analysis (DAPA) program of the International Center for Tropical Agriculture (CIAT), a not-for-profit agriculture, biodiversity and ecosystems research center, supported by the Consultative Group of International Agricultural Research (CGIAR), with headquarters in Cali, Colombia is looking for a visiting researcher to work on various modeling projects, primarily

Dear R-lings, I did not know which list to post to, because it is a studentship so not really a job, so it did not fit the r-sig-jobs list .... and it is about devloping an extension package interfaced with R .... I hope I did not upset anyone. If so apologies. The Centre For Complex systems Analysis at the University of York (YCCSA) in UK in collaboration with Stockholm Environment

I am just starting to code in R and need some help as I am used to doing this in SAS. I have a dataset that looks like this: Chemical Well1 Well2 Well3 Well4 BOD 13.2 14.2 15.5 14.2 O2 7.8 2.6 3.5 2.4 TURB 10.2 14.6 18.5 17.3 and so on with more chemicals.... I would like to transpose my data so that it looks like this: Chemical WellID Value BOD Well1 13.2 BOD Well2 14.2 BOD Well3 15.5 BOD

Dear R users, I have 2 SpatialPointsDataFrame's, pcs and East. The column str_1 in the first (pcs) is: > pcs[0:4,] coordinates cat str_1 int_1 int_2 dbl_1 dbl_2 1 (101000, 263000) 1 "SM06B" 101000 263000 4.978915 -4.293668 2 (101000, 265000) 2 "SM06C" 101000 265000 4.960478 -4.266742 3 (101000, 267000) 3 "SM06D" 101000 267000

Dear R, the condition: identical(length(x),1) returns FALSE but print(length(x)) returns 1 and: is.vector(x) is TRUE. is.integer(length(x)) is TRUE length(x) ==1 is TRUE I am puzzled. Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk

Dear Rfriends, what is the option --enable-memory-profiling at configuration (just before build + install) time? I did not find mention of it in the R admin manual (http://cran.r- project.org/doc/manuals/R-admin.html). Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645,