r_nought {exactLTRE}

R0, the net reproductive output

Description

The net reproductive output, R_0, is the expected number of offspring for one individual across their expected lifespan. It is calculated as the largest eigenvalue of the matrix product of the fertility matrix and the fundamental matrix. The fundamental matrix, generally referred to as N, contains the expected number of timesteps that an individual will spend in each age, stage, or size class of the matrix.

Usage

r_nought(Amat, Fmat)

Arguments

Amat

The full population projection matrix

Fmat

The fertility elements of the population projection matrix.

Value

The net reproductive output, a single value, is the number of offspring that an individual is expected to have over their lifespan.

Examples

A1<- matrix(data=c(0,0.8,0, 0,0,0.7, 5,0,0.2), nrow=3, ncol=3)
F1<- matrix(0, nrow=3, ncol=3)
F1[1,3]<- A1[1,3]
#F1 is all zeros, except the upper right corner which matches A1 for adult fertility
R0<- r_nought(A1, F1)