I think these models are extremely suspect, with nil predictive value. Where you have sustained exponential growth dynamics, as here, the results are fantastically sensitive to the parameters which go in the exponent, which in this case you can't predict with enough accuracy. The simplest ODE is something like: du/dt = k(t) * u(t) Whose solution locally looks like (for slow-varying k(t)) u(t) ∝ e^{ k(t) * t } One pos…
Well put. A 'predictive model' should say 'if you do X then you will end up with Y' - and the X cannot be adjusting some number. The X has to be stuff like 'building ETU's in West Africa', or 'canceling all flights',... A predictive model should be able to say 'don't bother canceling flights, it's no use - instead do this...'. Note: I'm going to be teaching a course in Erlang programming next month where the homework…
This is just wrong. A predictive model does not necessarily have any "action" input. Example: weather forecast.