The effect of serial day on the measurement of positivity and emotional complexity in diary studies

We study the effects of a diary's serial day (the number of days from the beginning of the study) on participants’ ( n = 2022) reports about positive and negative affect (NA). We find that (1) the number of reported positive events and the number of reported negative events decrease with serial day; (2) positivity increases with serial day: Reported Positive Affect (PA) increases, and reported NA decreases; (3) emotional complexity—the tendency...