Example of Policy Calculations for Supersession Chain with Bilateral Relationships
This topic provides an example of how policy calculations are done for items in a supersession chain with bilateral relationships.
For a bidirectional supersession chain, the horizon for average daily demand is adjusted according to the effective dates of the items.
Consider a bidirectional supersession chain with items A, B, C, and D. All days of the week are working days. The horizon for average daily demand is 30 days.
The effective dates for the item relationships are listed in this table:
| From | To | Relationship Start Date | Relationship End Date |
|---|---|---|---|
| A | B | 01-Jan-23 | 31-Jan-23 |
| B | C | 01-Feb-23 | 28-Feb-23 |
| C | D | 01-Mar-23 | – |
After the forecast is generated by the replenishment plan, the effective dates for the items are calculated as depicted in this table:
| Item | Item Start Date | Item End Date |
|---|---|---|
| A | 01-Jan-22 The start date is the history start date for the plan. |
31-Dec-22 |
| B | 01-Jan-23 | 31-Jan-23 |
| C | 01-Feb-23 | 28-Feb-23 |
| D | 01-Mar-23 | 31-Dec-23 The end date is the end date of the planning horizon for the plan. |
The forecast is generated for items within their effective dates. The horizon for average daily demand is computed on the basis of the start and end dates for each item and is reduced when it's effective for less than 30 days (the specified value for the horizon for average daily demand in the policy assignment set). If the plan start date is 15-Jan-23, then the horizon for average daily demand is as depicted by this table:
| Item | Item Start Date | Item End Date | Horizon |
|---|---|---|---|
| A | 01-Jan-22 | 31-Dec-22 | – |
| B | 01-Jan-23 | 31-Jan-23 | 16 days |
| C | 01-Feb-23 | 28-Feb-23 | 28 days |
| D | 01-Mar-23 | 31-Dec-23 | 30 days |
After the average daily demand is calculated according to the horizon for average daily demand, the policy values are calculated for the items.