Intermittency and Obsolescence: a Croston Method With Linear Decay

Only two Croston-style forecasting methods are currently known for handling stochastic intermittent demand with possible demand obsolescence: TSB and HES, both shown to be unbiased. When an item becomes obsolescent then TSB’s forecasts decay exponentially, while HES’s decay hyperbolically. We describe a third variant called Linear-Exponential Smoothing that is also unbiased, decays linearly to zero in a finite time, is asymptotically the best variant for handling obsolescence, and performs well in experiments.