The transit assignment has been enhanced to support line specific boarding times. The introduction of this new feature responds to a need which was expressed by many users in the past. For the first time it is now possible to include an additive line specific cost component which is paid once by all travelers using the line, regardless of where they board the line and how long they stay on board. This opens new or improved modeling possibilities in cases where line or mode specific factors are important in the route choice. A typical example where line specific boarding times are useful is the modeling of express lines which charge a premium fare. Also, mode or operator specific boarding times can be used (by using the same value for all lines of the same mode or operator) to reflect differences in fare or comfort.
This new possibility complements the previously available choices of constant or node specific boarding times. It is activated by the modified select question
Select: Source for boarding times
1= same value for entire network
2= node specific boarding times
3= line specific boarding times
4= node and line specific boarding times
Note that the selections 1 and 2 correspond to the previous implementation,
so that this change in the dialog will not cause any compatibility problems
with existing macros.
Since in the assignment model based on optimal strategies, the boarding to all lines passing at the same node is handled integrally, strictly speaking the model does not allow for line specific boarding times. As no such restrictions apply at the alighting node, these times are actually implemented at the ``alighting'' times, which is equivalent from a mathematical point of view, since boarding and alighting necessarily occur to and from the same line.