Ridership data is available as a separate network object in Visum. The individual ridership data represent the individual sections of the surveyed path. The ridership data set can contain one or more items of ridership data. The data set number links the ridership data to a ridership data set. The index specifies the order of the path legs. There is a relation from a ridership data item to all ridership data of the same data set, which can be used to retrieve common information (e.g. the boarding stop of the first data item of this data set). Ridership data can have user-defined (data and formula) attributes. Here, for example, the user can enter the ticket type collected or the group of people encountered.
Each ridership data item has a two-part key consisting of the data set number and the index. The key must be unique across the demand segments.
The survey path leg is indicated using a special attribute. If this does not happen, the first path leg is assumed to be the survey path leg. A ridership data item has two calculated attributes for the output of the survey line status and overall status, as well as a calculated attribute for the output of the flag actually used (survey "E", pre-survey leg "V", post-survey leg "N").
The following data is required for ridership data and the consistency conditions must be met:
- The departure time, including the day, must be known for a data set's ridership data item. The day can be specified by date or start day index. If this information is not available, the first day of the calendar is selected. This is always the case in models without a calendar. If a ridership data item is marked as a survey path leg, a time must always be specified (unless a vehicle journey is specified).
- Each ridership data item must contain either BoardStopNo and AlightStopNo or SurveyVehJourney, BoardVehJourneyItemIndex and AlightVehJourneyItemIndex. In the second case, the indices must be vehicle journey item indices of the vehicle journey designated by SurveyVehJourney. If vehicle journey items are selected, the stops result from this and are shown in the list.
- If no special information about the input stop is given, the boarding stop is taken as the input stop.
- All information on network elements can only refer to elements present in the network model. Keys of network elements (e.g. stops, lines, vehicle journeys, etc.) that are not present in the model are not used. Corresponding data sets may not be checked for plausibility.
- Ridership data does not require a reference to the origin and destination zones.
- All details that refer to the entire path and therefore have the character of header data can be specified multiple times and even contradictorily. In the plausibility check, the ridership data with the smallest index wins.
