Notation

Description

Forecast at the beginning of moth t of demand in month t

dt

Demand in month t

Forecast in month t of number of months between consecutive positive demands (CR, SBA)

kt

Number of months since the last positive demand at the beginning of month t (CR, SBA)

Forecast of demand in month t, provided this demand is positive (CR, SBA, TSB)

Forecast of the probability of a positive demand in month t (TSB)

pt

Indicator variable that indicates whether or not there is a positive demand in & month t (TSB)

α, β

Smoothing constants (0 ≤ α, β ≤ 1)