similar to: temporal and spatial pseudorreplication with lmer

Folks; I have looked for this subject extensively using all the resources I have available and could not find a solution; therefore I am sending you this email seeking for help. I need to solve a discontinuous nonlinear function, but R 2.6 keeps giving me an error. Below is a simple example: f <- function (t,k,l,u) { r0<-346.1 x<-t-l if (x<0) r0 else (r0-u)*exp(-k*x)+u

I am currently attempting to hack the recently featured profileModels package so that it can handle models generated by the lme4 (mixed models) package. I'm getting really confused by different behavior of summary() before and after loading the lme4 package, and inside and outside the profileMethod() function. The basic behavior is that with lme4 loaded, and "obj" a fitted object

Hi I have the following formula (I hope it is clear - if no, I can try to do better the next time) h(x, a, b) = integral(0 to pi/2) ( ( integral(D/sin(alpha) to Inf) ( ( f(x, a, b) ) dx ) dalpha ) and I want to do an mle with it. I know how to use mle() and I also know about integrate(). My problem is to give the parameter values a and b to the

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

Hello everybody, I am beginning with loops and functions and would be glad to have help in the following question: If i have a dataframe like this Site Prof H 1 1 24 1 1 16 1 1 67 1 2 23 1 2 56 1 2 45 2 1 67 2 1 46 And I would like to create a new column that subtracts the minimum of H from H, but for S1 and P1 only

I have measured values for 47 chemicals in a stream. After processing the original data frame through reshape2, the recast data frame has this structure: 'data.frame': 256 obs. of 47 variables: $ site : Factor w/ 143 levels "BC-0.5","BC-1",..: 1 1 1 2 2 2 2 2 2 2 ... $ sampdate : Date, format: "1996-04-19" "1996-05-21" ... $ Acid :