multiresultm {popbio} | R Documentation |
This function generates multinomial random numbers for state transitions and lognormal or binomial (for clutch size=1) random numbers for fertilities and returns a vector of the number of individuals per stage class at t+1.
multiresultm(n, T, F, varF=NULL)
n |
the vector of numbers of individuals per class at t |
T |
a transition T matrix |
F |
a fertility F matrix |
varF |
a matrix of inter-individual variance in fertilities, default is NULL for simulating population where clutch size = 1, so that fertilities give the probabilities of birth. |
The function returns a vector of the number of individuals per class at t+1.
Adapted to R by Patrick Nantel.
Adapted from Matlab code in Box 8.11 in Morris and Doak (2002) and section 15.1.3 in Caswell (2001)
Caswell, H. 2001. Matrix population models. Construction, Analysis and interpretation. 2nd ed. Sinauer, Sunderland, Massachusetts.
Morris, W. F., and D. F. Doak. 2002. Quantitative conservation biology: Theory and practice of population viability analysis. Sinauer, Sunderland, Massachusetts, USA.
data(whale) multiresultm(c(1,9,9,9),whale$T, whale$F) multiresultm(c(1,9,9,9),whale$T, whale$F) ## create graph similar to Fig 15.3 a reps <- 10 # number of trajectories tmax <- 200 # length of the trajectories totalpop <- matrix(0,tmax,reps) # initializes totalpop matrix to store trajectories nzero <- c(1,1,1,1) # starting population size for (j in 1:reps) { n <- nzero for (i in 1:tmax) { n <- multiresultm(n,whale$T,whale$F) totalpop[i,j] <- sum(n) } } matplot(totalpop, type = 'l', log="y", xlab = 'Time (years)', ylab = 'Total population')