ABIT (Activity Based Incremental Travel demand model) is an activity-based agent-based transport model developed by the Professorship of Travel Behavior at the Technical University of Munich. It generates travel demand individually for every person in the study area and updates incrementally over time with the integration of a land use model. The demand generated are a tour plans consisting of chains of activities and trips over a weekly period.
Model flowchart (See it in our miro board)
The following table summarizes the model components of ABIT:
| Model | Purpose* | Dependent variable | Model type | Data source** | |
|---|---|---|---|---|---|
| 1 | Habitual mode choice | No purpose | Habitual mode | Nested logit model | MOP |
| 2 | Activity generation | Mandatory | Number of days with activity per week | Zero Inflated Model (Binary logit + Ordered logit) | MOP |
| 3 | Activity generation | Discretionary (accompany and recreational round trips) | Number of activities per week | Zero Inflated Model (Binary logit +Negative Binomial) | MOP |
| 4 | Activity generation | Discretionary (shopping, recreation and other) | Number of activities per week | Negative Binomial | MOP |
| 5 | Main activity destination choice | Discretionary (and mandatory if no information exists) | Destination zone | Multinomial logit (based on distance to home) | MOP (only for calibration to match trip distances) |
| 6 | Stop destination choice | Discretionary (and mandatory if no information exists) | Destination zone | Multinomial logit (based on distance to previous and after activities) | MOP (only for calibration to match trip distances) |
| 7 | Split into stops on mandatory tour and other | Discretionary | Mandatory stop or other | Binary logit | MOP |
| 8 | Split discretionary activities on discretionary tours | Discretionary | Primary or stop on discretionary | Rule-based | MOP |
| 9 | Split into stop before/stop after | Discretionary | Before or after | Weighted sampling based on start time cumulative probability | MOP |
| 10 | Start time and duration | All | Start time and duration | Weighted sampling from empirical distributions (joint duration and start distributions) | MOP |
| 11 | Tour mode choice | Mandatory | Mode | Nested logit | MOP |
| 12 | Tour mode choice | Discretionary | Mode | Nested logit | MOP |
| 13 | Subtour generation | All | Makes subtour or not | Binary logit | MOP |
*Mandatory: work, education. Discretionary: accompany, recreation, shopping, other.
**MOP: German Mobility Panel data.