## 3 Results  
### Characteristics of Perceived Personal Control  
The responses to the perceived controls (with a response rate above 99% for all control types) are presented in Figure 2. In general, noise, ventilation and temperature were perceived as poorly controlled. Regarding shading from the sun and lighting, the occupants reported the perceived control as moderate. A group of people (up to 35%) declared \"no control\" can be observed for all control parameters. For temperature and ventilation control, the rest of the occupants are equally distributed in the five levels of control degree. Very few occupants seem to be able to control the noise level at their workstation, where answers follow a descending rate (full control below 5%). On the contrary, regarding lighting and shading from the sun, after the distinctive \"no control\" group, the occupants' answers exhibited an ascending rate, indicating that they feel more able to control the light conditions (full control up to 20%).  
Figure 3 presents the percentages of the office occupants who have no or low perceived control (values \(<\) 4) on their indoor working environment. The majority (63%) has no or low control on noise. Half of them declared no or low control on ventilation (53%) and temperature (47%). Almost one-third of them remarked that they do not have satisfactory levels of control for lighting and shading from sun conditions.  
In Figure 4, the responses are presented based on the occupancy per room. Responses were categorized into five groups. In the first group, which is characterized by personal office rooms, occupants seem to have higher levels of control, except for ventilation. It is interesting to note that as the occupancy increases, the degree of personal control becomes lower. Offices with many occupants (30+), probably open space offices, show the lowest degrees of personal control for all parameters. Furthermore, in all groups, the occupants characterized noise control as the worst parameter, while lighting and shading from the sun control gathered higher degrees of control.  
Figure 1: Schematic overview of the methodology used.  
The satisfaction comfort towards IEQ parameters was also examined, with regard to their respective control options. The perceived satisfaction parameters were categorized in three levels of perceived control: no control (1), low control (2-3), high control (\(\geq\)4) and are presented in Figure 5. For each IEQ parameter, the related personal control option was selected, e.g., for parameters about temperature satisfaction, temperature control was selected; for indoor air quality parameters, ventilation control  
Figure 4: Mean degree of perceived control according to room occupancy (1 = no control, 7 = full control).  
Figure 3: Percentage of occupants who reported no or low control.  
Figure 2: Percentage of occupants based on self-reported degree of control (\(n=7441\)).  
was selected, etc. Occupants with high degrees of personal control over their working environment reported higher levels of satisfaction on average. In all cases, occupants with high perceived control reported higher satisfaction levels. Occupants without personal control evaluated satisfaction of the IEQ with lower levels. Only in some cases, 'none' and 'low personal' control options are reversed, e.g., in the case of satisfaction with odor and reflection.  
Figure 6 shows the degree of personal control vs. self-reported productivity at the workstation (\(n=7289\)) and in other places in the building (\(n=7154\)). In both cases, occupants with higher levels of personal control reported higher levels of productivity (Kruskal Wallis: \(p<0.001\)). Regarding the workstations, a small increase in the low control area results in a clear increase in productivity.