Table 1 Notations
Symbol | Description |
|---|---|
t | Time or period |
\(\hat{D}_{t}\) | The expected demand |
\(D_{t}\) | The actual demand i.e. the incoming orders |
\(I_{t}\) | The actual inventory level |
\(I_{t}^{*}\) | The desired inventory level |
\(AI_{t}\) | The adjustment for the inventory level |
\(SL_{t}\) | The actual supply line (orders placed but not yet received) |
\(SL_{t}^{*}\) | The desired supply line |
\(ASL_{t}\) | Adjustment for the supply line |
\(O_{t}\) | Order quantity |
\(\delta\) | The desired coverage |
\(\gamma\) | The expected (or perceived) lag between ordering and acquisition of goods |
\(\theta\) | A constant which determines how fast expectations are updated, \(0 \le \theta \le 1\) |
\(\alpha_{I}\) | Rate at which the discrepancy between actual and desired inventory levels is corrected, \(0 \le \alpha_{I} \le 1\) |
\(\alpha_{SL}\) | The rate at which the discrepancy between actual and desired supply line is corrected, \(0 \le \alpha_{SL} \le 1\) |