2.1.2 Inventory Models
The economic order-quantity (EOQ) model considers the trade-off between ordering cost and storage cost in
choosing the quantity to use in replenishing item inventories. A larger order-quantity reduces ordering frequency,
and, hence ordering cost/month, but requires holding a larger average inventory, which increases storage
(holding) cost/month. On the other hand, a smaller order-quantity reduces average inventory but requires more
frequent ordering and higher ordering cost/month. The cost- minimizing order-quantity is called the Economic
Order Quantity (EOQ). This builds intuition about the robustness of EOQ, which makes the model useful for
management decision-making even if its inputs (parameters) are only known to be within a range of possible
values. This also provides intuition about choosing an inventory-management system, not just an EOQ [8].