in the same position and will not, as would be the case if the system were only marginally stable or entirely unstable, continue to move away from the bottom of the ladle under this constant force equal to its weight. It is important to note that in this example the system is not stable for all inputs. Give the marble a big enough push, and it will fall out of the ladle and fall, stopping only when it reaches the floor. For some systems, therefore, it is proper to state that a system is exponentially stable over a certain range of inputs. See also Marginal stability Control theory State space (controls) References External links Parameter estimation and asymptotic stability instochastic filtering, Anastasia Papavasiliou∗September 28, 2004 Dynamical systems Stability theory fr:Stabilité de Lyapunov#Les stabilités