### Name: BOD ### Title: Biochemical Oxygen Demand ### Aliases: BOD ### Keywords: datasets ### ** Examples require(stats) # simplest form of fitting a first-order model to these data fm1 <- nls(demand ~ A*(1-exp(-exp(lrc)*Time)), data = BOD, start = c(A = 20, lrc = log(.35))) coef(fm1) print(fm1) # using the plinear algorithm fm2 <- nls(demand ~ (1-exp(-exp(lrc)*Time)), data = BOD, start = c(lrc = log(.35)), algorithm = "plinear", trace = TRUE) # using a self-starting model fm3 <- nls(demand ~ SSasympOrig(Time, A, lrc), data = BOD) summary( fm3 )