10.1: Prelude to Factorial Designs

Have you heard the the phrase "cleanliness is next to godliness"? Schnall et al. (2008) wanted to test if judgments of morality differed by the cleanliness of the room in which the judgments were made. In an experiment, Schnall et al. (2008) manipulated participants’ feelings of disgust by testing them in either a clean room or a messy room that contained dirty dishes, an overflowing wastebasket, and a chewed-up pen. The cleanliness of the room was their IV. Schnall et al. (2008) also used a self-report questionnaire to measure the amount of attention that people pay to their own bodily sensations, which Schnall et al. (2008) called this “private body consciousness.” Because Schnall et al. (2008) thought that private body consciousness would affect their DV, private body consciousness was another IV. Schnall et al. (2008) measured their primary dependent variable, the harshness of people’s moral judgments, by describing different behaviors (e.g., eating one’s dead dog, failing to return a found wallet) and having participants rate the moral acceptability of each one on a scale of 1 to 7. As a manipulation check, Schnall et al. (2008) also asked participants to rate their current level of disgust and other emotions. The primary results of Schnall et al. (2008) was that participants in the messy room were, in fact, more disgusted and made harsher moral judgments than participants in the clean room—but only if they scored relatively high in private body consciousness.

Schnall et al. (2008) is an example of a factorial design, a study with multiple IVs that are systematically combined to see how each combination affects the DV.

References

Schnall, S., Haidt, J., Clore, G. L., & Jordan, A. H. (2008). Disgust as embodied moral judgment. Personality and Social Psychology Bulletin, 34, 1096–1109.