. Author manuscript; available in PMC: 2014 Oct 21.

Published in final edited form as: J Mod Opt. 2013 Oct 10;60(14):1200–1208. doi: 10.1080/09500340.2013.845700

Table 1.

Mean seasonal light data: daylight hours (sunrise to sunset), integrated solar radiation from the pyranometer (lux-hours), and daily hours spent outdoors and indoors from sensor data and questionnaire estimates. Sensor data and questionnaire estimates pairs significantly different at p < 0.03 (**) and p < 0.01 (*) (two-tailed t-tests).

	Season
Metric	spring	fall	winter
Mean hours of daylight	12.68 ± 0.18	10.15 ± 0.15	11.26 ± 0.19
Total solar lux-hours	1.30 × 10⁷	4.70 × 10⁶	6.94 × 10⁶
Mean outdoor exposure hours: light sensor	1.57 ± 1.22 *	1.27 ± 1.18 *	1.23 ± 1.18 *
Mean outdoor exposure hours: estimate	4.00 ± 1.42 *	3.35 ± 1.85 *	4.15 ± 1.93 *
Mean indoor exposure hours: light sensor	11.12 ± 1.23 **	8.88 ± 1.17 *	10.03 ± 1.19
Mean indoor exposure hours: estimate	12.14 ± 2.66 **	13.20 ± 1.48 *	10.35 ± 2.60