ScotsPine {nlrwr} | R Documentation |
Leaf area indices were calculated for Scots Pine trees in a region of Estonia.
data(ScotsPine)
A data frame with 14 observations on the following 2 variables.
age
lai
Piegorsch, W. W. and Bailer, A. J. (2005) Analyzing Environmental Data, Chichester: John Wiley & Sons (p. 93).
## Plotting data plot(lai~age, data=ScotsPine, xlab = "Age (years)", ylab = "Leaf area index" ) ## Fitting the mono-exponenetial model expFct <- deriv3(~a+b*exp(-age/c), c("a","b","c"), function(a,b,c,age)NULL) exp.m1 <- nls(lai~expFct(a, b, c, age), data=ScotsPine, start=list(a= 1, b=1 ,c=10)) ## Calculating curvature measures rms.curv(exp.m1)