## 3 Results
### Within-Subject Analysis (Follow-Up POE Investigation)
#### 3.1.2 Subjective Comparison  
Descriptive statistics--Descriptive statistics analysis for all 15 satisfaction variables shows that the mean values of all variables except 'Glare sun' (satisfaction with glare from the sun at the moment) and 'A-artificial' (annual satisfaction with artificial lighting) were a bit lower for the second POE in June compared to October. On average, for the satisfaction values, the change was 0.4 points. This means people were more satisfied with the built environment in general in June (1 = very satisfactory, 7 = very unsatisfactory). Similarly, in October, the highest satisfaction belonged to'satisfaction with the job', which increased slightly in June. Then,'satisfaction with daylight' (both 'annually' and 'at the moment') had the highest satisfaction rate in June (\(M\) = 2.3, \(SD\) = 1.5). Satisfaction with daylight 'at the moment' with a 1.8 point improvement from October shows the highest increase in satisfaction. The least satisfaction in June belonged to artificial light (\(M\) = 3.5, \(SD\) = 1.58). See Table 6 for more details on other variables.  
Paired samples \(t\)-test--To determine whether there is statistical evidence that the mean difference between paired observations on a particular outcome is significantly  
Figure 4: Overview of the results for the mean value of (**a**) horizontal illuminance of the calculated sensor points of the ten rooms’ areas at the work plane height (E\({}_{\text{h-room}}\)), (**c**) horizontal illuminance on the task area of the calculated sensor points of the ten rooms’ areas (E\({}_{\text{h-task}}\)), and (**e**) mean value of vertical illuminance in the center point of each room with viewing direction towards the daylight opening of the ten rooms (E\({}_{\text{v}}\)) under three different sky conditions for 11 October and 4 June both for 10 a.m. (**a,c,e**). The details of the mean values under clear sky condition (**b,d,f**).  
Figure 5: (**a**) DGP values under clear sky (blue), overcast sky (red), and intermediate sky (green) conditions: imperceptible level (DGP < 0.3), perceptible level (0.3 < DGP < 0.35), disturbing glare (0.35 < DGP < 0.4), intolerable glare (DGP > 0.45); (**b**) The details of the mean values under clear sky condition.  
different from zero, a paired sample \(t\)-test was run for ten participants who filled out the questionnaire two times during early October and June. The results show that, although the mean satisfaction values are increased from October to June for almost all variables, a significant difference was only found in scores for natural light from October to June (_sig_ = 0.016, \(M\) = 1.80, \(SD\) = 1.93). In addition, a marginally significant difference was found for 'A-Glare sun' (_sig_ = 0.052, \(M\) = 0.50 \(SD\) = 0.71) and 'Light desk' (_sig_ = 0.053, \(M\) = 0.80 \(SD\) = 1.13).  
Correlation analysis--The results show that there were'very strong' (0.8 \(<\) \(r\) \(<\) 1) to'strong' (0.6 \(<\) \(r\) \(<\) 0.79) degrees of correlations for all the variables between annual and at the moment evaluations except for 'Natural light' in October. In June (\(N\) = 10), the highest correlation was found for 'Glare sunlight' (0.95, \(p\) \(<\) 0.01) and 'Glare artificial light' (0.92, \(p\) \(<\) 0.01). This means that participants either perceived glare as similar all year round or found it hard to recall the difference between glare at the moment and annually.