## 3 The Integral Role of Lighting in Urban Environment
### Correlation Between Individual Aspects and Sn Coefficient Value  
Sn is derived as a basic subjective measure that combines two subjective factors. It is a quantitative measure of the impact of the current state. Knowing its value gives us entry-level information about a location, but most importantly, it warns us of situations that are inappropriate, indicate an inappropriate economic situation due to excessive energy consumption, or indicate possible light pollution. When looking at the evaluation results, as shown in Figure 3, we have relatively consistent values for the psychological and the aesthetic-functional factor. Only the sociological factor with the usage intensity aspect deviates slightly from the movement of the values of the other aspects. It is understandable that the coincidence is not absolute, as we are dealing with statistically determined values. The validity of the sustainability coefficient Sn is also confirmed by the existing correlation between Sn and subjective indicators of environmental comfort. Figure 4 shows the correlation between psychological, sociological, aesthetic-functional factors and the Sn. The strength and direction of these relationships can provide insight into how changes in these aspects might affect Sn. The factors related to psychological aspects generally show a moderate correlation with Sn, whether positive or negative. Aesthetic-functional factors show varying correlations with Sn, with \"comfort\" showing the strongest positive relationship. As already shown in Figure 4, the correlation coefficient now confirms once again that sociological factors, in particular \"Usage Intensity\", appear to have a negligible relationship with Sn. Since we cannot prove the correlation between Sn and the sociological factor as a whole, we check whether there is at least a partial connection between Sn and individual activities. The results in Figure 5 show a very high positive correlation between Sn and the activities \"playing\" and \"sitting\". In contrast, the correlation with \"walking\" is almost negligible. The activity \"socializing\" also shows a moderate positive correlation, but this is weaker compared to \"playing\" and \"sitting\". The results obtained are not surprising and are in line with [PERSON]'s theory. [PERSON] [49] (pp. 11-14) introduced a method based on probability theory to understand the effects of the physical environment on behavior. He hypothesized that the physical environment can influence the number of people using open spaces, the duration of individual activities, and the type of activities that occur. He categorized activities into three groups: \"Necessary activities\" (mandatory, with no choice for participants), \"Optional activities\" (voluntarily chosen by individuals) and \"Social activities\" (those that arise spontaneously under appropriate spatial conditions). Walking is a necessary activity that is carried out in all cities and under all spatial conditions, including spatial illumination. The relationship with Sn is therefore negligible. Socializing is an optional activity and shows a stronger positive  
Figure 4: Display of Pearson product-moment correlation coefficient (r) of individual aspects and Sn. Figure 5: Display of Pearson product–moment correlation coefficient (r) between individual activities and Sn. correlation with Sn. Playing and sitting are social activities that show the strongest positive correlation with Sn. When reviewing the assessment of individual locations, we find the following situations for cases when it is Sn < 1.00:  
(a) illuminance intensity is sufficient, but the location is not perceived as attractive enough (example L1 Gosposka Street), a complete architectural redesign is needed to increase Sn;  
(b) the illuminance is too high, the location is otherwise perceived as attractive (example L3 Kocljeva Street), a lower illuminance is required to increase Sn;  
(c) the illuminance intensity is not sufficient, and the location is not perceived as attractive (example L7 Liberty Square).