Detecting spatial features from data-maps: the visual intersection of data as support to decision-making

The assessment of spatial systems can be supported by the analysis of data coming from different sources and describing different aspects such as economic, social, environmental, energy, housing or mobility issues. Nevertheless, the analysis of such a large amount of data is difficult. In order to improve the readability of data also with non-technicians, new methods of communication are needed, which could facilitate the sharing of information among people with different skills and backgrounds. In this context, the paper shows the developments in geo-visualisation to support and improve the processes of planning and decision-making. First, the use of a map-based visualisation is suitable for intuitively understanding the location and distribution of specific elements. Second, the graphic interface can be used to drive users in the investigation of data. It can provide a linear method that is more comprehensive to the human mind in dealing with the complexity of spatial systems. In addition, the possibility to select and filter data by single attributes allows databases to be explored interactively and read by differently skilled users. The intersection and overlapping of information enables users to discover the relationships between data, the inefficiencies and critical areas, thus providing suggestions for further reasoning in planning and decision-making. Furthermore, collaborative and participatory sessions require quick answers and simple readability. Thus, the real time response to simple queries widens the opportunities for improving the discussion. A case study describes the methodology used for sharing the data collected during an Interreg IVB NWE Project named "CoDe24" (INTERREG IVB NWE, 2005; ERDF European Territorial Cooperation 2007-2013, 2010). By the use of a web-GIS visualisation tool, namely GISualisation, the project partnership was allowed to explore the data concerning the railways and train typologies along the Genoa-Rotterdam corridor. Despite the high factor of usability of the tool, it was not employed much by participants to the project so that further reasoning is needed to evaluate how digital tools are perceived by professionals