Demand models aim at describing peoples’ behaviour that leads actual trip making between origins and destinations using specific modes in specific periods. Common modelling approach is to divide this process into three components:
- Trip generation: how many trips are being made?
- Trip distribution or destination choice: where are they going to?
- Modal split or mode choice: which mode are they using?
In case of 24-hour models a fourth component is introduced: Time of day or Period choice, in which period of the day do they travel?