A Comparison of Spatio-temporal Interpolation Methods to Estimate Speed Information

Bıçakçı Yunus Serhat, Sarıca Beytullah, Pakdil Mete Ercan, Yazırlı Batuhan, Demirel Hande


Road transport, especially congestion, contributes about one-fifth of the European Union (EU)’s total emissions of carbon dioxide (CO2), and considered as one of the major source global greenhouse gas emissions. There are many efforts to reduce these impacts. However, this is a challenging task, since data, tools, methods and systems are not mature even lacking to support decision making process. With this respect especially speed information is vital, but not integrated into transport models. The speed information is currently available via Information and Communication Technology (ICT) Infrastructure, so the possibility of introducing speed data into transport model should be explored. Hence, the aim of the study is to integrate speed data into TRANS-TOOLS model, which is the major model used for transport policy analysis in EU. In order to integrate the speed data, a frame-work is designed and spatial interpolation methods namely, spatial overlay, buffering and inverse distance weighting (IDW) are compared to estimate speed information.
The major contribution of this study is to model the temporal dimension of the speed data that is lacking in the typical spatial analyze tools. The initial results are promising, where all speed information is associated to the TRANS-TOOLS network and values are simulated hourly. According to the initial results, spatial analyze methods could successfully fill the gap in the transport model and could aid policy making process.

Keywords: Geographic Information Systems (GIS), congestion, carbon emissions, spatial interpolation methods