Model glossary

State variable: quantity describing the system at a given time.

Parameter: quantity controlling a model relationship or rate.

Deterministic model: fixed initial conditions and parameters determine a unique trajectory.

Stochastic model: random components allow different outcomes under the same specified conditions.

Discrete-time model: state is updated at separated time points.

Continuous-time model: time varies continuously.

Equilibrium: state at which the deterministic rate of change is zero.

Stability: behaviour of trajectories after small perturbations from a state or solution.

Calibration: adjustment of unknown parameters to selected observations.

Validation: evaluation of whether a model is adequate for its stated purpose.

Simulation: computational generation of model behaviour.

Sensitivity: change in model output caused by changes in inputs or parameters.