## 3 Methodology and Database
The key goal of the indirect acquisition phase is to develop a sophisticated Network Dataset structure. After confirming the topology of the road network, this structure merges the vector database with linear geometry (representing Romania's road network) and the attribute database (detailing the length of each road segment in meters). Such integration establishes the essential spatial database that is vital for the formulation of the spatial analysis model. Figure 1: Diagram of the methodological process flow. The stage of spatial analysis represents the most elaborate segment of the methodology, offering a variety of techniques for territorial investigation. These techniques are integrated in a manner that accentuates the unique aspects and impacts of each factor analyzed in determining the final estimated potential risk of road accidents. The spatial analysis process is structured into three distinct sub-stages: Exploratory Analysis, Network Analysis, and Integration Analysis. The outcomes from these sub-stages, beyond providing spatial representations of the analyzed issues, also serve as databases for the subsequent sub-stage, thereby contributing to the refinement of the proposed model. At the core of the spatial analysis is the determination of the distance to each type of traffic incident identified in the field. To enhance the understanding of each incident's impact in the risk assessment process, an exploratory analysis of the traffic incident database was conducted. This involved consultations with representatives from traffic safety institutions (such as Traffic Police Directorate, local police, and others), leading to the classification of traffic incidents into five principal categories. These categories consider factors like the severity of incidents, their patterns of occurrence, weather conditions, traffic restrictions in the incident area, and the existing traffic signal system. This classification aims for a more precise integration into the model (Figure 1). The exploratory analysis involves conducting a basic spatial analysis, which includes querying the attribute table to generate point vector spatial databases for each type of incident. This results in 23 point vector structures, which then become the primary database for the next substage. The network analysis leverages spatial databases obtained both indirectly and through exploratory spatial analysis to pinpoint areas within the territory that are significantly affected by traffic incidents. The methodology adopted for quantifying impact involves analyzing the distance to the incident site, with a greater distance indicating a lower impact and a shorter distance indicating a higher impact. This network analysis was conducted using ArcGIS Pro, specifically employing the Network Analyst module and the Service Area function. The primary input databases for the Service Area spatial analysis consisted of the Network Dataset and the 23 point vector structures representing different types of traffic incidents. To assess the territorial impact, distance intervals were established as follows: 0-200 m, 200-500 m, 500-700 m, 700-1000 m, 1000-2000 m, 2000-2500 m, 2500-5000 m, 5000-10,000 m, 10,000-100,000 m, and over 100,000 m. These intervals were selected based on the specific characteristics and layout of Romania's road network. The integration of databases resulting from network analysis forms the core of the proposed methodology. This integration relies on applying Multi Criteria Decision Analysis (MCDA) techniques, which are designed to address spatial analysis challenges by weighting various contributing factors (in this case, the impact of different types of road incidents). Among the MCDA methods, the Analytic Hierarchy Process (AHP) was selected for implementation within a GIS environment. This is facilitated through the extAhp 2.0 extension within ArcGIS 10.8. AHP, a semi-quantitative method introduced by [PERSON] [64], is utilized for weighting the analysis of databases.