lvsimdata.time {capn} | R Documentation |
Prey-Predator (Lotka-Volterra) example in LV dataset
Description
The lvsimdata.time
provides the time simulation data in LV
dataset to simulate prey-predator (Lotka-Volterra) model. The original code was written by Joshua Abbott in MATLAB and Seong Do Yun adapted it to a package example. The prey-predator model is:
Prey (X
): \dot{X} = rX \left( 1 - \frac{X}{K} \right) - aXY - \theta X
, and
Predator (Y
): \dot{Y} = bXY - mY - \gamma Y
.
The parameters are given as:
r = 0.025
: intrinsic growth rate for prey,
K = 1
: carrying capacity for prey,
a = 0.08
: predator-related mortality parameter for prey,
b = 0.05
: predator/prey uptake parameter for predator,
m = 0.01
: natural mortality for predator,
\gamma = 0.005
: slope for linear predator harvest control rule, and
\theta = 0.005
: slope for linear prey harvest control rule
The predator with no economic value (unharvested) is designed for the economic program as:
W = harv.prey(p.prey-c.prey/X)\theta X + harv.pred*(p.pred-c.pred/Y)\gamma Y
.
The paramters are:
p.pred = 0
: price per unit harvest of predator,
p.prey = 25
: price per unit harvest of prey,
c.prey = 0.1 p_prey
: cost /per unit of prey effort in Schaefer model (really c/q with q=1), and
c.pred = c_prey
: cost per unit of predator effort in Schaefer model (really c/q with q=1).
Usage
## Load dataset
data("lvdata")
Format
lvsimdata.time: a data for time simulation (101 ODE solution)
-
tseq
time sequence from 0 to 100 -
xs
prey stock -
ys
predator stock