“…For example, tracking call history would enable assessment of social network size and frequency of contact—the two major components of social isolation scales (Petersen, Thielke, Austin, & Kaye, 2015). Other behaviors that may relate to loneliness that can be tracked unobtrusively include time spent outside the home (Petersen et al, 2014; Petersen, Austin, Mattek, & Kaye, 2015), computer use (Amichai-Hamburger & Ben-Artzi, 2003), and sleep quality (Hawkley et al, 2010). Such approaches to loneliness identification would have dramatic consequences for the understanding of loneliness, enabling researchers to monitor and assess loneliness levels on smaller timescales such as daily or even hourly.…”