Calculates the generation time for an age or stage-classified demographic projection matrix.
gen.time(A, peryear = 5)Demographic projection matrix.
Width of the age classes.
The generation time implied by the demographic projection matrix.
Calculates the generation time (T) for an age or stage-classified demographic projection matrix using the identity:
Ro = exp(r*T)
where Ro is the net reproduction number and r is the intrinsic rate of increase = log(lambda).
Generation time is the amount of time that it takes a typical female to produce Ro offspring or, equivalently, the amount of time it takes a population growing with instantaneous rate r to increase by a factor of Ro.
Keyfitz, N., and Caswell. H. (2005). Applied mathematical demography. 3rd ed. New York: Springer.
Caswell, H. (2001). Matrix population models: Construction, analysis, and interpretation. 2nd ed. Sunderland, MA: Sinauer.
Preston, S.H., Heuveline, P. and Guillot, F. (2001). Demography: Measuring and modeling population processes. Oxford: Blackwell.