similar to: empirical maximum likelihood estimation

Dear R-community My ODE problems looks as follows: (1) dA/dt = u*A - v*B (2) dB/dt = v*B - u*A where u is a constant, and v=k*t (k=constant, t=time) Does anybody knows a good function/procedure of solving? Should one involve the equation (3) dv/dt = k? Thanks for your support. -- Dominik Heinzmann Master of Science in Mathematics, EPFL Ph.D. student in Biostatistics Institute of Mathematics

Dear all, I would like to compare two distance matrices to find the correlation between those and create a XY plot.could you please kindly help me and let me know how I can do that using R.(Mantel test?). Your help is very much appreciated!! Many thanks! Regards, Sima Fakheran ............................................................... Sima Fakheran Esfahani PhD Student Institute of

Hi everyone, Is it possible to use tapply(x,y,mean) if not all groups of x by y are of the same length (for example if you have one missing observation)? I tried tapply(x,y,mean,na.omit=T) but it doesn't work! Steffi -- --------------------------------- Stefanie von Felten Doktorandin ETH Z?rich Institut f?r Pflanzenwissenschaften ETH Zentrum, LFW A 2 Telefon: 044 632 85 97 Telefax: 044

Good afternoon! I would like to ask you about similarity measures and clustering in R for Binary data. Would you please kindly help me and let me know about that commands in R? Thanks in advance for your kind attentions. I look forward to hearing from you as soon as possible. Best regards, Sima

Hi there, I am running MCMCpack (MCMCirt1d model) on some files (26 items x about 800 – 1200 individuals). I have a problem. When I am working on “big” files, the R program crashes. More precisely I got the following Microsoft Warning: ******************************************* Microsoft Visual C++ Runtime Library Runtime Error! Program: C:\Program Files\R\R-2.4.1\bin\Rgui.exe

I'm using an SVM as I've seen a paper that reported extremely good results. I'm not having such luck. I'm also interested in ideas for other approaches to the problem that can also be applied to general problems (no assuming that we're looking for spirals). Here is my code: library(mlbench) library(e1071) raw <- mlbench.spirals(194, 2) spiral <-

Dear All, I am analysing a dataset on levels of herbivory in seedlings in an experimental setup in a rainforest. I have seven classes/categories of seedling damage/herbivory that I want to analyse, modelling each separately. There are twenty maternal trees, with eight groups of seedlings around each. Each tree has a TreeID, which I use as the random effect (blocking factor). There are two

Hi everyone, Can someone explain me how to calculate SAS type III sums of squares in R? Not that I would like to use them, I know they are problematic. I would like to know how to calculate them in order to demonstrate that strange things happen when you use them (for a course for example). I know you can use drop1(lm(), test="F") but for an lm(y~A+B+A:B), type III SSQs are only

Hi, there! I finally became a disciple of 'R', after having lost years of my life handling data with a popular, rather wide-spread spreadsheet-software. Now I want to plot the results of many runs of my simulation over time, so that the means +/- Standard error are on the y-axis, and time on the x-axis. I have tried 'boxplot', with timesteps as the grouping variable, but did

Dear all! After hours of trying around, I gave up: I have a 2-dimensional array, and I know how to split it into its rows and how to get the mean for every row using 'sapply'. But what I want is to calculate the mean over the first n rows, and then the second n rows, etc., so that I get a vector like: v == mean1(row 1:5), mean2(row6:10),... (trivial, you might say. I find it rather

Dear Sir/ Madam, I would like to ask you about mantel test in R. In ade4 package, if I want to use mantel.rtest, I get error massage "Object of class to "dist" expected". As I already have two dissimilarity matrices, shall I again compute distance measure using this function? If not, could you please let me know which function/command I can use to do? Thank you very much in

Hi all, I am trying to find estimates for 7 parameters of a model which should fit real data. I have a function for the negative log likelihood (NLL) of the data. With optim(method="L-BFGS-B",lower=0) I am now minimizing the NLL to find the best fitting parameters. My problem is that the algorithm does not converge for certain data sets. I have read that one should scale the fn

Dear all, is this a bug or do a miss something (this concerns version 0.63.1 on Linux)? > boxplot (c (1, 2, 3, 4, 5), ylim= c (-5, 5)) Warning: parameter "ylim" couldn't be set in high-level plot() function > boxplot (c (1, 2, 3, 4, 5), pars= list (ylim= c (-5, 5))) Warning: parameter "ylim" couldn't be set in high-level plot() function > and actually in

Dear all, this is a rather basic question; i am not sure how to structure my data well: I want to extraxt various measures from my raw-data. These measures are of different sizes, so I decided to store them in a list, like: run1 <- list(Dom = (my_vector), mean = (my_single_number)) I can do that in a for loop for 40 runs, ending up with 40 lists: run1, run2, ..., run40. To have all the

Dear all, I would like to use the biological symbols for male and female as plotting symbols in a scatterplot (ideally filled and non-filled). R does not seem to have these symbols using pch= in plot() nor are they implemented via expression() or at least I did not find them. I found that the symbols are e.g. available in the wasysym and the marvosym package in LaTeX. I have coded two very rough

Dear all, I would like to use the biological symbols for male and female as plotting symbols in a scatterplot (ideally filled and non-filled). R does not seem to have these symbols using pch= in plot() nor are they implemented via expression() or at least I did not find them. I found that the symbols are e.g. available in the wasysym and the marvosym package in LaTeX. I have coded two very rough

Dear all, well, today I just seem to run into these problems ... (I am still working on R 0.63.1 on a SuSE 5.2). I would like to have a data.frame that also contains character (and NOT factor) vectors. Two things that I tried (the second worked in R 0.62.2): > test.df <- data.frame (X= character (4)) > test.df$X [1] <- "a" Warning: invalid factor level, NAs generated or:

> Apart from ipa are there any other good tools out there for centralised user > auth? I am currently testing LDAP (openldap) combined with nss_ldap, configured with authconfig. I would start by testing IPA. Redhat is building out a set of enterprise management tools which include cobbler and spacewalk; I would think IPA will eventually be integrated into their mgt tools. That said, if

Dear all, Many thanks to all who always so quickly respond with helpful hints! Currently I am working with R 0.63.1 on SuSE 5.2 which I installed this morning within about half an hour: my deepest compliments to the developpers! (I had still 0.62.2 before.) This time I am trying the following: > xy <- list (a= c (1, 2, NA), b= c (2, 3)) > list.name <- "xy" > get

Dear all, The following works with a simple result of lm but gives the error with a more complicated one (could this be due to singularities that occurr in the model?). > cooks.distance (X) Error: NAs in foreign function call (arg 6) > class (X) [1] "lm" But, actually, I would like to ask a more general question: Is there a place (I searched in the CRAN site) where I find