Supplemental Material for When Did This Happen? Indicators of Accuracy for Dating Recent and Remote Personal Events

Memory for time is often imperfect. We investigated indicators of dating accuracy for recent and remote personal events. In Study 1, 78 participants dated approximately 20 events from the past three to eleven weeks, and in Study 2, 40 participants dated approximately 25 events three to five years old. For date verification, events were obtained from participants’ partners, who kept a diary (Study 1) or retrieved events from personal records (Study 2). In both studies, we found that confidence, dating strategy indicating known dates, and a direct connection with temporal landmarks were associated with higher dating accuracy. High importance, direct experience, and events embedded within extended periods indicated higher dating accuracy for recent events; high vividness was associated with higher dating accuracy for remote events. Our results suggest that confidence, dating strategy, and phenomenological characteristics can provide useful indication of dating accuracy.