The study does not account for the fact that some people simply choose to spend their free time by themselves and do not indulge in &#x27;social&#x27; activities. Including the average size of the participant&#x27;s social circle and how they chose to spent their free time could have been useful.<p>I am sure a lot of people who travel around by themselves or spend the weekend(s) hiking&#x2F;biking their favorite trail, etc. do not really rely on their free time coinciding with others&#x27;.<p>Thoughts?