## 5 Discussion  
We will now conduct a more detailed analysis and discuss the obtained results, highlighting the key findings. Additionally, we will compare the results obtained by BTOPSIS with the responses to question QSL. Figure 6 shows the cities ranked according to the results of the multi-criteria analysis, reflecting various aspects of urban living and residents' satisfaction determined by the BTOPSIS method with initially set up utility function, i.e., \(BT(0.7;\ 0.4)\). Figure 6: Ranking of European cities based on quality of life, determined by the BTOPSIS method. Source: Table 6.  
From Table 6 and Figure 6, it can be seen that the level of satisfaction with living in the city, as measured by BTOPSIS, varies significantly across cities, including within the same country. The BTOPSIS scores ranged from 0.4154 for Tirana to 0.7295 for Zurich, indicating that no city excelled or fell behind across all criteria. Among the 83 cities included in the survey, Zurich is ranked first with the highest percentage of respondents who selected \"Very satisfied\" with public transport (75.98%) and health care services (65.98%). However, Zurich ranked 12 th in the percentage of respondents \"Very satisfied\" with public spaces (33.69%) and 10 th in those \"Very satisfied\" with green spaces (47.21%). Groningen is close behind the second position with a BTOPSIS of 0.6941. Among the surveyed cities, the highest proportion of Groningen's citizens indicated being \"Very satisfied\" with schools and other educational facilities (55.21%). Groningen also ranked second in the percentage of respondents \"Very satisfied\" with health care services (55.80%). However, Groningen placed 32 nd in the percentage of citizens \"Very satisfied\" with public transport (30.48%). At the bottom of the city rankings is Tirana, where the highest position it achieved among respondents who selected \"Very satisfied\" was 40 th, in relation to schools and other educational facilities (22.85%). In contrast, it ranked 81 st for those \"Very satisfied\" with cultural facilities such as concert halls, theaters, museums, and libraries (13.5%), and 80 th for public transport satisfaction, with only 8.3% of respondents expressing that they were \"Very satisfied\". Skopje ranks 82 nd with a BTOPSIS score of 0.4381. Among the surveyed cities, it occupies the 67 th position for respondents who answered \"Very satisfied\" with sports facilities (15.97%). However, it ranks last at 83 rd for those who are \"Very satisfied\" with healthcare services (4.28%). The largest intra-country differences are observed in Italy, where Bologna (48 th) and Palermo (81 st) show a score difference of 0.1580, followed by Turkiye, with a notable gap between Antalya (41 st) and Istanbul (76 th), resulting in a difference of 0.1151. France also exhibits significant variation between Rennes (10 th) and Marseille (71 st), with a score difference of 0.1138, while in Romania, Cluj-Napoca (44 th) and Bucharest (77 th) differ by 0.1059. Noticeable intra-country variation is also evident in Spain, between Oviedo (33 rd) and Madrid (69 th), with a score difference of 0.0762, and in Poland, between Bialystok (14 th) and Krakow (58 th), with a difference of 0.0746. In Germany, the gap between Munich (6 th) and Berlin (39 th) amounts to 0.0688. Smaller but still significant differences are seen in the Netherlands, between Groningen (2 nd) and Rotterdam (28 th), with a score difference of 0.0573; in the United Kingdom, between Cardiff (8 th) and London (40 th), with a gap of 0.0519, and in Belgium, where Antwerp (22 nd) and Liege (51 st) have a difference of 0.0487. Table 8 presents descriptive statistics for BTOPSIS values, divided by groups of countries, highlighting variations in key indicators across different regions. Cities in the northern (0.6501) and western (0.6349) Member States report slightly higher levels of life satisfaction on average compared to those in the eastern (0.5923) and southern (0.5433) Member States.