Perceived entitativity is the central causal mechanism through which homogeneity and essentialism drive stereotyping.

Evidence

Spencer- Rodgers, Hamilton, et al. (2007) investigated the role of entitativity, and other group-relevant concepts, in stereotyping. Participants rated four social categories (e.g., Latinos) and four task groups (e.g., juries) on scales assessing perceived entitativity, homogeneity, essence (boundedness, inductive potential, meaningfulness, stability, naturalness, and inalterability; Haslam et al., 2000), role differentiation (extent that there is role delineation among group members and behaviors typical of group members), and agency (ability to act collectively and effectively). They also rated the groups on 38 attributes, and for each group, eight of the attributes were (based on pretesting) stereotypic of that group. Analyses showed that perceived entitativity directly predicted stereotyping for each of the eight groups. In addition, although the other group-related variables also predicted (at least to some degree) stereo typing, mediational analyses showed that entitativity significantly mediated the effects of those variables—homogeneity, essentialism, role differentiation, and agency—on stereotyping. Finally, additional analyses showed that the relationship between perceived entitativity and stereotyping was not mediated by homogeneity, essentialism, role differentiation, and agency. These findings led Spencer-Rodgers, Hamilton, et al. to conclude that entitativity plays a central role in stereotyping and group perception more generally. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 279

Categorization

• XREF: Directly corroborates the reader’s prejudice-psychology thread: this gives the mechanistic ordering — homogeneity and essentialism predict stereotyping only BECAUSE they compose entitativity, a clean causal claim to contrast with other models that treat essentialism as the prime driver.
• QUESTION: If entitativity mediates essentialism’s effect on stereotyping for both ethnic categories AND ad hoc juries, what then does ‘groupness’ per se add over essence — i.e., is inferred cohesion doing the load-bearing work that ‘natural kindness’ claims were thought to do? Worth chasing.
• corroborated: 2 independent passages support this claim — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 279