Resilience of the Metro of Porto and Accessibility of POIs: A Network Science Approach

Over the past decades, tourism in Portugal has grown exponentially, particularly in major cities such as Porto. As a result, ensuring smooth mobility for tourists and providing them with efficient access to the city's main points of interest is important. This issue not only affects tourists but also directly impacts on the daily lives of Porto residents. To this end, this Master's Final Work goal is to address two research questions: "How resilient is Porto's Metro system?" and "To what extent are Points of Interest (POIs) in Porto accessible via the Metro?". To assess the Metro's resilience, simulations were conducted by removing stops based on betweenness centrality, degree centrality, and random removal strategies, in addition to considering percolation thresholds. These simulations were carried out using network science techniques, specifically analyzing the largest connected component of the Metro network. To evaluate the accessibility of POIs via the Metro, the walking distance between Metro stops and the POIs was calculated. This analysis was based on a 15-minute walking threshold to determine the Metro's coverage of major attractions. The findings related to the first research question show that Porto's Metro system lacks resilience to targeted disruptions at stops with high betweenness and degree centrality, leading to an almost immediate impact on the connectivity of the Metro lines. In contrast, randomly selected stop removals exhibit a more stable pattern, causing a more gradual decline in network connectivity. Regarding the second research question, the results reveal that Metro stops cover at least 71.75% of the city's main points of interest under the applied thresholds. These insights could influence transportation planning in Porto and may also be extended to other cities significantly affected by increasing tourism.