A current state of an item being tracked by an item-tracking system may be determined using prior state information about the item. To ensure proper temporal order of the state information, software events triggered by physical events associated with the item are received from a reader at an event interpretation system. A database or queue within the event interpretation system holds the software events for a delay time determined by a maximum transmission delay time of the software events. A sorter within the event interpretation system orders the software events relative to one another so as to correspond to an order of the physical events. An association model of the event interpretation system may determine state information related to the item for storage in a state information database. Accordingly, system exceptions in the item tracking system may be reduced, and an accuracy and reliability of the system may be improved.