The importance of the reliability of the input: why the investment in the purchase of a network and demand matrices always pays off!

Written by Antonello Racina

A model is a set of mathematical laws and relations able to treat the characteristics of a given phenomenon and allow the knowledge of its probable evolution in time. Mathematical models, applied to transportation supply systems, use:

·      graph and network theory to represent the topological and functional structure of infrastructure supply;

·      mathematical laws and relations to describe the "performance" and the mutual influence of the elements that compose it.

Simplifying, we can assert that they aim to provide a description of the demand-supply interaction. 

Demand and infrastructural supply constitute the principal inputs of a transport model; therefore, it is necessary that they are adapted to the representation of the reality that is the object of the simulation.

The collection of the input, however, constitutes the more important and delicate phase of the construction of a model. Even if the structure of this last one turns out to be valid, if the data had been collected in an inaccurate way, the result of the simulation will inevitably be wrong.

The construction of a graph that well represents a system of transport demands has to be composed of:

·      the definition of the elements that constitute it (nodes and links);

·      the functional characterization of links and nodes.

Building it from scratch or basing it on opensource resources, requires a long phase of verification and characterization of the elements that does not guarantee the accuracy of the result. Just think of medium-small networks that can be made up of as many as 50.000 links, checking and validating them "manually" is labour-intensive and at risk of "human" error.

TomTom MultiNet is the most comprehensive solution on the market, consisting of a high-quality road graph. It provides detailed information about the directionality of links, intersections, and functional and geometric characteristics. MultiNet networks are georeferenced and continuously updated based on data from numerous sources around the world. 

To support the road graph, and to validate the modelling process, TomTom has been collecting anonymous measurements based on GPS data from its users worldwide since 2008. TomTom has created a database of historical traffic data that is completely unique in the industry, based on trillions of measurements and it is able to provide information about the traffic situation on the road network. The main statistics it provides are average and median speed, speed limits, road names and their functional class and speed percentiles. 

The subject of traffic demand is also a relevant one, and it would be difficult and time-consuming to carry out surveys (questionnaires administered via telephone or digital interviews, along the road or at traffic lights, or surveys of license plates) to determine an Origin-Destination matrix that well represents the mobility that characterizes an area and a specific period.

TomTom can provide a solution to this problem as well. Complex algorithms have been developed and validated to analyze enormous quantities of "Floating Car Data" and identify travel dynamics.

Ultimately, the solutions offered by TomTom are a guarantee of quality and savings in days of work.

If you are interested in these solutions, please contact me at the following email address [email protected] or contact us at: https://citieu.pagedemo.co/