To summarize vital rates within stage classes, we can use the Growth, shrinkage, stasis, dormancy, fecundity, or clonality. Or more vital rates (sometimes called ‘lower-level vital rates’).Īssuming a post-breeding census design, we can retroactively break apartĮach transition rate into at least two vital rate components: survival,Īnd ‘something’ conditional on survival. The transition rates that make up MPMs generally reflect products of two Shape_surv( lt $ lx) # based on lx trajectory prior to the QSD #> -0.06573764 Standardized vital rates Shape_surv( lt $ lx) # based on full lx trajectory #> -0.04681254 # calculate the shape of the survival/mortality trajectory This quantity can thenīe used to subset age trajectories of mortality or fertility to periodsĮarlier than the QSD, so as to avoid artefactual plateaus in mortality To reach the quasi-stationary distribution (QSD). Qsd_converge() can be used to identify the time it takes for a cohort Trajectories derived using age-from-stage methods. Some MPMs are parameterized with a stasis loop at the maximum stageĬlass, which can lead to apparent plateaus in mortality or fertility Shape_rep( lx) # shape of fecundity trajectory #> 0.3097147 Life tables and the quasi-stationary distribution Shape_surv( lx) # shape of survival/mortality trajectory #> -0.04681254 # first derive age-trajectories of survivorship (lx) and fecundity (mx) lx 0.9077186Įntropy_d( lx, mx) # Demetrius' entropy #> 2.062862 Start = 2 to set our starting stage class of interest to the ‘small’ In mpm1 is a ‘seed’ stage, which we might considerįunctionally-distinct from the ‘above-ground’ stages, we’ll specify Of life’ for the purposes of calculation.
Which is used to specify the stage class that represents the ‘beginning One of the most common arguments among functions in Rage is start, The object mpm1 is a list containing two elements: the growth/survivalĬomponent of the MPM (the U matrix), and the sexual reproductionĬomponent (the F matrix).
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