Overview
In order to develop effective transport policies, reliable statistical data and modelling tools are needed to estimate future developments and support the decision-making process. This can help in assessing needs for transport infrastructure and evaluating the likely effects of policy actions.
Many models of the transport system require knowledge of the sources and destinations of passengers and goods, structured in 'origin-destination' matrices. However, data on origins and destinations are often not available, at least publicly, particularly for international flows. This has become a problem in Europe with the reduction in customs/border controls as part of the Single Market developments. Also, data are often inconsistent between countries, which creates difficulties in assessing policy towards international traffic and the Trans-European Transport Network. Therefore, new methods are needed to derive these origin-destination matrices.
The aim of OD-ESTIM was to provide methods for constructing flow data for inter-regional passenger and goods transport, in a cost-efficient way, based on economic data for each region. This was decided on the premise that adequate economic data are often accessible when transport flow data are missing.
Funding
Results
Methods were devised for estimating both passenger and freight transport flows, based on a quantification of the relationship between socio-economic variables and the associated demand for transport. The methods operate at the NUTS-2 level used in statistics, which generally corresponds to the administrative regions of a country. Origin-destination data are produced, disaggregated by transport mode and type of commodity for freight, and by mode and trip purpose for passenger transport.
Both methods were calibrated on data for France and The Netherlands, and then tested on data for Spain and Italy. In general terms, the validation results were better for the Spanish case than for Italy. This could relate to the availability of more extensive data for Spain, but it may also reflect the different characteristics of these countries (such as the current modal shares and the relative importance of different sectors of the economy).
Due to the limited availability of transport data (especially for long-distance flows), the calibration of the passenger method could not be fully validated. However, the method does give acceptable results for highly aggregate information, such as the total generation of trips by region.
Policy implications
The project concluded that direct collection of transport data provides the best basis for policy decisions. However, the OD-ESTIM methods do provide an adequate, fast and economical procedure where such data are not available. This is particularly relevant to EU Member States that do not yet collect detailed data on inter-regional flows, and for Central and Eastern European countries that need to evaluate investment in strategic infrastructure (such as the extension of the TEN-T network eastwards). The methods could also be used in developing countries that receive EU aid for new infrastructure.
One limitation of the new methods is that they give estimates only for the fraction of total traffic on transport links that consists of long-distance traffic. Surveys indicate that up to 70% of daily traffic may relate to short-distance intra-regional traffic. This means that to get a complete view of transport demand, this short-distance traffic should be added to the results from the OD-ESTIM methods.
OD-ESTIM highlighted the need to assemble data on long-distance international passenger transport, with consistent data collection across different countries.