gompertz: Gompertz model with log-normal observations.
Description
gompertz is a pomp object encoding a stochastic Gompertz population model with log-normal measurement error.
Usage
data(gompertz)
Arguments
Details
The state process is $X_{t+1} = K^{(1-S)} X_{t}^S \varepsilon_{t}$, where $S=e^{-r}$ and the $\varepsilon_t$ are i.i.d. lognormal random deviates with variance $\sigma^2$.
The observed variables $Y_t$ are distributed as $\mathrm{lognormal}(\log{X_t},\tau)$.
The model is parameterized by the logarithms of $r$, $K$, $\sigma$, and $\tau$;
the initial condition is parameterized directly.
See Also
pomp-class and the introductory vignette vignette("intro_to_pomp").