search for: breakpoint0seg2t

Displaying 1 result from an estimated 1 matches for "breakpoint0seg2t".

2006 Nov 16
0
nmle for time of structural change?
...far been unable to get 'nlme' to work for me. The following toy example is the closest I've come to what I want using 'nlme': library(nlme) tstDF5 <- data.frame(t.=rep(1:5, 3), subj=rep(1:3, e=5), y=c(rep(0:1, c(1,4)), rep(0:1, c(2,3)), rep(0:1, c(3,2)) ) ) breakpoint0seg2t <- function(t., lT){ t1 <- 5*plogis(-lT) ((t.<=t1)+(t1<t.)) } tstFit <- nlme(y~breakpoint0seg2t(t., lT1), data=tstDF5, fixed=lT1~1, random=list(subj=pdDiag(l1~1)), start=0 ) Error in chol((value + t(value))/2) : the leading minor of order 1 is not positive definite...