In this paper we propose a modified gravity model that takes into account that a population generally consists of heterogeneous groups, and we suggest a new statistical test for heterogeneity. We apply our new model to two real world data sets, and it turns out that this new model fits the data...

In western Norway, fjords cause disconnections in the road network, necessitating the use of ferries. In several cases, ferries have been replaced by roads, often part-financed by tolls. We use data on commuting from a region with a high number of ferries, tunnels and bridges. Using a...

Maximum entropy methods are used to infer the true trip-distribution matrix in cases where parts of the data are suppressed due to privacy concerns. Large proportions of the suppressed data are found to be inferred correctly when the marginal totals in the trip distribution are known....

In many cases fjords cause disconnections in the road network, calling for the service of ferries. The construction of bridges or subsea tunnels may, however, substitute the ferries, often financed by toll charges. In this paper we use data on commuting flows from a Norwegian region with a high...