PTV Visum - Frequently Asked Questions (FAQs)

(#VIS31729)

Is an example available for the Procedure 'Estimate gravitation parameters (KALIBRI)'?

Example file: https://www.ptvgroup.com/faq-files/PTV_Visum20_How_to_calibrate_a_gravity_model.zip
This demonstrates the necessary steps:
- Assignment
- Skim matrix calculation
- Create a histogram, classifiy to obtain the shares per interval. (Demand = matrix 25, classification matrix = matrix 26)
- Save from the histogram the intervals for Kalibri: Matrix histogram -> Save intervals. Note: Share = 0 for the first and the last interval.
- Setup the Procedure 'Estimate gravitation parameters (KALIBRI)': Tab 'Distribution' -> Read from file (use the saved intervals)
This example estimates the parameter c for the Demand stratum 'HW_Emp', stored in an respective attribute.