“…Participants were recruited through email. During the ~ 30-day experiment, participants (i) wore a wrist sensor on their dominant hand (Q-sensor, Affectiva, USA) to measure 3-axis acceleration (ACC), skin conductance (SC), and skin temperature (ST) at 8 Hz; (ii) installed an Android phone application using the funf open source framework [7] to measure timing of calls, timing of short message service (SMS), location, and timing of screen-on; (iii) wore a wrist actigraphy monitor on their non-dominant hand (Motion Logger, AMI, USA) to measure activity and light exposure levels every 1 minute; and (iv) completed a sleep diary every morning to record bed time, sleep latency, wake time, and the number and timing of awakenings. The sleep diary was inspected by an experimenter every day to check completion and to obtain corrections or clarifications from the student if there were any clear errors or missing data.…”