Calculate shape of reproduction over age
Calculates a 'shape' value of distribution of reproduction over age by comparing the area under a cumulative reproduction curve (over age) with the area under a cumulative function describing constant reproduction.
shape_rep(rep, xmin = NULL, xmax = NULL)
rep |
Either 1) a numeric vector describing reproduction over age (mx),
or 2) a If x is not supplied, the function will assume age classes starting at 0
with time steps of unit. If x ends at maximum longevity,
|
xmin, xmax |
The minimum and maximum age respectively over which to
evaluate shape. If not given, these default to |
a shape value describing symmetry of reproduction over age by comparing the area under a cumulative reproduction curve over age with the area under constant reproduction. May take any real value between -0.5 and +0.5. A value of 0 indicates negligible ageing (neither generally increasing nor generally decreasing reproduction with age); positive values indicate senescence (generally decreasing reproduction with age); negative values indicate negative senescence (generally increasing reproduction with age). A value of +0.5 indicates that (hypothetically) all individuals are born to individuals of age 0; a value of -0.5 indicates that all individuals are born at the age of maximum longevity.
Iain Stott <iainmstott@gmail.com>
Baudisch, A, Stott, I. 2019. A pace and shape perspective on fertility. Methods Ecol Evol. 10: 1941– 1951. <https://doi.org/10.1111/2041-210X.13289>
Other life history traits:
entropy_d(),
entropy_k(),
gen_time(),
life_expect_mean(),
longevity(),
net_repro_rate(),
repro_maturity,
shape_surv()
# increasing mx yields negative shape mx <- c(0, 0, 0.3, 0.4, 0.5, 0.6) shape_rep(mx) # decreasing mx yields positive shape mx <- c(1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4) shape_rep(mx) # constant mx yields shape = 0 mx <- c(0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1) shape_rep(mx)
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.