Fig. 2
From: Unobtrusive measurement of cognitive load and physiological signals in uncontrolled environments
Metadata on (a) the countries of origin of the participants, and (b) the duration of data collected for each participant in the controlled environment (in 
), and in the uncontrolled environments (in 
). As can be seen in (a), the majority of participants identified Europe, South America, or Asia as their continent of origin, while the minority of participants identified North America or Africa as the continent of their origin. As depicted in (b), overall approximately 120 hours of recordings in the controlled environment and approximately 194 hours of recordings in the uncontrolled environments were collected for both the Muse S headband and the Empatica E4 watch in total.
