Figure 1. Dynamics of face-to-face interactions in the 2012 deployment.

The participants meet in the morning, attend classes within four different study lines, and interact across majors in the evening. Edges are colored according to the frequency of observation, ranging from low (blue) to high (red). With 24 possible observations per hour, the color thresholds are respectively: blue ( observations ), purple ( observations ), and red ( observations). Node size is linearly scaled according to degree.