Who helped yesterday will help tomorrow: Trait and state components in prosocial goal realisation.

The present study aims to disentangle the state and trait components of prosocial goal realisation, defined as a set of personally meaningful prosocial actions undertaken in natural settings. Based on a diary study with seven daily measurements from 180 participants (a total of 1005 data points), we performed temporal variance decomposition using the STARTS model. The observed individual scores are explained by: ST-a common trait factor, capturing variance stable across days; ART-a unique autoregressive trait factor, capturing variance changing from 1 day to the next; and S-state factors, a series of uncorrelated factors reflecting occasion-specific variance. The results demonstrate the relative stability of prosocial goal realisation, extending the knowledge on the state/trait distinction in actual prosocial behaviour.