Population estimate of type of Bay Checkerspot butterfly
Estimates of the population of a type of Bay Checkerspot butterfly near San Francisco.
data(baycheck)
A data frame with 27 observations on the following 2 variables.
a numeric vector
estimated number
From chapter 4 of Morris and Doak, Quantitative Conservation Biology: Theory and Practice of Population Viability Analysis, Sinauer Associates, 2003.
data(baycheck)
plot(Nt ~ year,baycheck)
## fit Ricker model N_{t+1} = N_t e^{-rt}W_t
n = length(baycheck$year)
yt = with(baycheck,log(Nt[-1]/Nt[-n]))
nt = with(baycheck,Nt[-n])
lm(yt ~ nt,baycheck)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.