Validating the Affect Grid: Evidence from daily diary data

The Affect Grid is a single-item measure that simultaneously assesses affective valence and arousal, yet few studies have tested its validity in everyday settings. Prior validation efforts focused on only one dimension, used small samples, and/or relied on cross-sectional data. To address these gaps, we integrated two week-long daily diary studies (N = 474; 2,809 observations) in which participants reported their nightly affect using both the Affect Grid and single-item ratings of how positive, negative, neutral, and aroused they felt. Correlation analyses showed that Affect Grid valence and arousal were strongly related to their corresponding single-item measures but only weakly related to other dimensions, supporting convergent and discriminant validity. Multilevel models further showed that Affect Grid valence predicted higher positive and lower negative affect, whereas Affect Grid arousal primarily predicted single-item arousal, at both between- and within-person levels. A quadratic pattern for valence suggested that neutral affect peaked at moderate levels of valence, consistent with the view of valence as a bipolar continuum. Overall, these results support the Affect Grid as a concise and reliable tool for measuring affective valence and arousal in daily life.