Fig. 4.

Predicted duration of social activity (per day) for individuals engaged in social activity at least once. Social activity duration is shown to be dependent on intraindividual sleep duration and how much sleep one obtained on average during the study, split by type of day. In this figure, we exemplify the predicted effect of a change in interindividual sleep duration for three example sleepers. Note that each line does not represent any individual participant, but rather the predictions made by the model for a particular length of average sleeper as arbitrarily defined as follows. An average sleeper was defined as an individual whose average was equal to the mean of all participants (473 min, i.e., 7 h 53 min). A short sleeper was defined as an individual whose average sleep duration was two SDs (39 min) below the mean of all participants’ mean sleep durations. Therefore, for this model, a short sleeper is someone who averages 394 min (6 h, 34 min) or less of sleep per night. A long sleeper was defined as an individual whose sleep duration was two SDs above the sample mean, in other words, someone who averaged 551 min (9 h, 11 min) or more of sleep per night. To increase ease of interpretability, the predicted sum of daily 30-min periods of social activity have been converted to hours. Error ribbons represent pointwise 95% CIs.