Moral and Affective Film Set (MAAFS): A normed moral video database.

Moral psychology has relied nearly exclusively on text stimuli in the development and testing of theories. However, text stimuli lack the rich variety of morally-relevant social and contextual cues available in everyday interactions. A consequence of this pervasive ecological invalidity may be that moral psychological theories are mischaracterized by an overreliance on cue-impoverished moral stimuli. We address this limitation by developing a cue-rich Moral and Affective Film Set (MAAFS). We crowd-sourced videos of moral behaviours, using previously validated text stimuli and definitions of moral foundations as a guide for content. Crowd-sourced clips were rated by 322 American and 253 Australian participants on a range of moral and affective dimensions, including wrongness, moral foundation relevance, punishment, arousal, discrete emotion-relevance, clarity, previous exposure, and how weird/uncommon the moral acts were. The final stimulus set contained sixty nine moral videos. Ratings confirmed that the videos are reliably rated as morally wrong and feature a variety of moral concerns. The validation process revealed features that make the MAAFS useful for future research: (1) the MAAFS includes a range of videos that depict everyday transgressions, (2) certain videos evoke negative emotions at an intensity comparable to mood induction films, (3) the videos are largely novel: participants had never seen more than 90% of the videos. We anticipate the MAAFS will be a particularly valuable tool for researchers in moral psychology who seek to study morality in scenarios that approximate real-life. However, the MAAFS may be valuable for other fields of psychology, for example, affective scientists may use these videos as a mood induction procedure. The complete stimulus set, links to videos, and normative statistics can be accessed at osf.io/8w3en.