Fig. 2.

This figure displays the combined trigonometric (non-significant) and linear (significant) functions underlying the periodicity in diary completion by day of the 30-day diary cycle holding constant the trigonometric function identified in completion by day of week (i.e., Fig. 1) as well as demographic and behavioral confounding variables. The gray histogram demonstrates the observed percentage of completed diaries by day of diary cycle, while the black line is a plot of the estimated probability of completion based on the marginal fixed effects of the final model. The difference between the observed and predicted probabilities is largely the result of adjusting for demographic confounding within the model