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) |