Project objectives

Project objectives

Special focus is on increasing the level of detail with regard to the rail, maritime and air transport modules. The aim here is to better analyse issues of cost, capacity and externalities of transport. An improved impact assessment model is also being developed, as well as a more precise model of impacts of road transport with regard to energy use, emissions and safety.

Resources are also devoted to improving the usability of the model. This is fairly straightforward since the present user interface and technical structure is by now very well known and has received very heavy use over the past 3-4 years. As such, there exists very detailed and precise knowledge about which aspects of the current modelling framework works well for users and which aspect that can be improved in that respect. As a result, resources are focused on improving those aspects that have been criticised.

The final model of TT3 will be IPR free as far as possible and more open than the present model. The model builds on the ArcGIS (ESRI) and Traffic Analyst Software (Rapidis). The tool-box approach is being continued by making the model flexible for expert users. Also, a wide range of standard configurations are provided for different types of policy analyses, which will make it much easier for end-users to apply the model. Focus is on making the model more efficient with regard to calculation time, yet without compromising on the scientific validity with regard to causal relationships and described transport behaviour.

Model objectives

The incremental development of the TT2 model means unfortunately that there is not a single report that documents the model scientifically. As some of the core modules originate back from before TT1, it is very difficult for a new user to get an overall understanding of the model framework. The present project develops a completely new thorough scientific documentation as well as a user guide which will be much more detailed than previously and build on experiences from maintaining the discussion forum and from conducting training classes. As model implementation is separated from model development within the consortium, the documentation as regard software implementation will mirror the exact mathematical structure of all model components. This can also be seen as a “model-protocol” which will make it easy for external partners to establish model linkages to TT3. All of the documentation will be validated and quality controlled in a multi-stage process.

Data objectives

The project will build on the new ETISplus data. Since this project will improve the existing data from TT2 and update them to 2010, we expect that the quality will be better than the present data. TENCONNECT2 will also increase the data foundation and these improvements will be integrated into the project.

Even so, the project assigns resources for further quality control of data and collection of new data. It is our experience that many problems with data are not realised until the model estimation and validation phase.

Software and user objectives

Our model philosophy is to build upon the well functioning parts of the existing model, and replace the parts of the models that are black boxes and/or cannot be sufficiently modified and calibrated to give good, or at least adequate, results.

The TT3 will be flexible in terms of both use and configuration. The user interface will have two levels, namely one simple interface for standard usage and a detailed interface where experienced users will be able to adjust and customize the model. In the simple user interfaces it will be easy to specify the model configuration.

The flexible configurations will allow improvements in both performance and level of detail, especially for modelling rail, maritime and air transport.

The model will be fully open and accessible. Prior black box parts of the model will be replaced. All models, data, parameters and configurations will be fully documented and adjustable