sim.Stasis.RW: Simulate trait evolution with a mode shift

In paleoTS: Analyze Paleontological Time-Series

Simulate trait evolution with a mode shift

Description

Trait evolution is modeled as a shift from a random walk (general or unbiased) to stasis, or vice versa.

Usage

sim.Stasis.RW(
  ns = c(20, 20),
  order = c("Stasis-RW", "RW-Stasis"),
  anc = 0,
  omega = 1,
  ms = 0,
  vs = 1,
  vp = 1,
  nn = 30,
  tt = NULL
)

Arguments

ns	vector of the number of samples in each segment
order	whether stasis or random walk come first, one of "Stasis-RW" or "RW-Stasis"
anc	starting trait value
omega	variance of stasis segment
ms	step mean during random walk segment
vs	step variance during random walk segment
vp	phenotypic trait variance for each population
nn	vector of sample sizes for each population
tt	vector of times (ages) for each population

Details

The anc argument is the starting trait value, and if the first segment is stasis, this is also the value of the stasis mean. When the first segment is a random walk, the stasis mean in the second segment is equal to the true trait mean at the end of the initial random walk.

Value

a paleoTSfit object

See Also

fitModeShift

Examples

x1 <- sim.Stasis.RW(omega = 0.1, ms = 5, order = "Stasis-RW")
x2 <- sim.Stasis.RW(omega = 0.1, ms = 5, order = "RW-Stasis")
plot(x1)
plot(x2, add = TRUE, col = "blue")
abline(v = 19, lty=3)

paleoTS documentation built on Aug. 9, 2022, 1:06 a.m.