It need hardly be repeated that no ~detailed~ statistical agreement with observation is to be expected from models which are based on admitted simplifications. But the situation is quite analogous to others where complex and interacting statistical systems are under consideration. What is to be looked for is a comparable pattern with the main features of the phenomena; when, as we shall see, the model predicts important features which are found to conform to reality, it becomes one worthy of further study and elaboration.--M.S Bartlett, 1960.
Stochastic Population Models in Ecology and Epidemiology