Hello, all. I have co-opted a number of functions that can be used to plot the hazard/survival functions and associated density distribution for a Gompertz mortality model, given known parameters. The Gompertz hazard model has been shown to fit relatively well to the human adult lifespan. For example, if I wanted to plot the hazard (i.e., mortality) functions:
pop1 <- function (t) { x=c(0.03286343, 0.04271132) a3<-x[1] b3<-x[2] shift<-15 # only considering mortality after 15 years h.t<-a3*exp(b3*(t-shift)) return<-h.t } pop2 <- function (t) { x=c(0.02207778, 0.04580059) a3<-x[1] b3<-x[2] shift<-15 # only considering mortality after 15 years h.t<-a3*exp(b3*(t-shift)) return<-h.t } ylab.name <- expression(paste(italic(h),"(",italic(a),")")) plot(seq(15,80,1),pop1(seq(15,80,1)),type='l',ylab=ylab.name,xlab='Age (years)',ylim=c(0,0.8)) lines(seq(15,80,1),pop2(seq(15,80,1)),lty=2) How may I test for a significant difference in the hazard parameters that define the mortality experience for these two populations? Thanks in advance. Regards, Trey ----- Trey Batey---Anthropology Instructor Division of Social Sciences Mt. Hood Community College Gresham, OR 97030 Alt. Email: trey.batey[at]mhcc[dot]edu -- View this message in context: http://r.789695.n4.nabble.com/significant-difference-between-Gompertz-hazard-parameters-tp4635018.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.