The model is a version of a gravity-type model in which the flow of shoppers from all residential zones (postal sectors) to shopping destinations depends on:

The propensity of shoppers to travel different times and distances to shop.

The attractiveness of alternative shopping locations ( which is a function of size, and many other factors – such as parking, layout, presence of key retailers, etc) and/or derived from past time series of shopping developments and surveyed change in shopping patterns.

The model ensures the number of shoppers adds up consistently to the total shoppers in each residential zone (postal sector) and the travel function is calibrated to to minimise the difference between calculated and surveyed shopper flows.

It can be run on a non-food shopping system , or on a grocery shopping system depending on the data available.