Social dominance orientation (SDO) is a personality trait measuring an individual's support for social hierarchy and the extent to which they desire their in-group be superior to out-groups. SDO is conceptualized under social dominance theory as a measure of individual differences in levels of group-based discrimination; that is, it is a measure of an individual's preference for hierarchy within any social system and the domination over lower-status groups. It is a predisposition toward anti-egalitarianism within and between groups.
Individuals who score high in SDO desire to maintain and, in many cases, increase the differences between social statuses of different groups, as well as individual group members. People high in SDO also prefer hierarchical group orientations. Often, people who score high in SDO adhere strongly to belief in a "dog-eat-dog" world. It has also been found that men are generally higher than women in SDO measures. A study of undergraduates found that SDO does not have a strong positive relationship with authoritarianism.
Social dominance theory
SDO was first proposed by Jim Sidanius and Felicia Pratto as part of their social dominance theory (SDT). SDO is the key measurable component of SDT that is specific to it.
SDT begins with the empirical observation that surplus-producing social systems have a threefold group-based hierarchy structure: age-based, gender-based and "arbitrary set-based", which can include race, class, sexual orientation, caste, ethnicity, religious affiliation, etc. Age-based hierarchies invariably give more power to adults and middle-age people than children and younger adults, and gender-based hierarchies invariably grant more power to one gender over others, but arbitrary-set hierarchies—though quite resilient—are truly arbitrary.
SDT is based on three primary assumptions: While age- and gender-based hierarchies will tend to exist within all social systems, arbitrary-set systems of social hierarchy will invariably emerge within social systems producing sustainable economic surpluses. Most forms of group conflict and oppression (e.g., racism, homophobia, ethnocentrism, sexism, classism, regionalism) can be regarded as different manifestations of the same basic human predisposition to form group-based hierarchies. Human social systems are subject to the counterbalancing influences of hierarchy-enhancing (HE) forces, producing and maintaining ever higher levels of group-based social inequality, and hierarchy-attenuating (HA) forces, producing greater levels of group-based social equality.
SDO is the individual attitudinal aspect of SDT. It is influenced by group status, socialization, and temperament. In turn, it influences support for HE and HA "legitimating myths", defined as "values, attitudes, beliefs, causal attributions and ideologies" that in turn justify social institutions and practices that either enhance or attenuate group hierarchy. Legitimising myths are used by SDT to refer to widely accepted ideologies that are accepted as explaining how the world works—SDT does not have a position on the veracity, morality or rationality of these beliefs, as the theory is intended to be a descriptive account of group-based inequality rather than a normative theory.
Early development While the correlation of gender with SDO scores has been empirically measured and confirmed, the impact of temperament and socialization is less clear. Duckitt has suggested a model of attitude development for SDO, suggesting that unaffectionate socialisation in childhood causes a tough-minded attitude. According to Duckitt's model, people high in tough-minded personality are predisposed to view the world as a competitive place in which resource competition is zero-sum. A desire to compete, which fits with social dominance orientation, influences in-group and outside-group attitudes. People high in SDO also believe that hierarchies are present in all aspects of society and are more likely to agree with statements such as "It's probably a good thing that certain groups are at the top and other groups are at the bottom".
Scale
SDO has been measured by a series of scales that have been refined over time, all of which contain a balance of pro- and contra-trait statements or phrases. A 7-point Likert scale is used for each item; participants rate their agreement or disagreement with the statements from 1 (strongly disagree) to 7 (strongly agree). Most of the research was conducted with the SDO-5 (a 14-point scale) and SDO-6. The SDO-7 scale is the most recent scale measuring social dominance orientation, which embeds two sub-dimensions: dominance (SDO-D) and anti-egalitarianism (SDO-E).
SDO-7 items
Dominance sub-scale Some groups of people must be kept in their place. It's probably a good thing that certain groups are at the top and other groups are at the bottom. An ideal society requires some groups to be on top and others to be on the bottom. Some groups of people are simply inferior to other groups. Groups at the bottom are just as deserving as groups at the top. (reverse-scored) No one group should dominate in society. (reverse-scored) Groups at the bottom should not have to stay in their place. (reverse-scored) Group dominance is a poor principle. (reverse-scored)
Anti-egalitarianism sub-scale We should not push for group equality. We shouldn't try to guarantee that every group has the same quality of life. It is unjust to try to make groups equal. Group equality should not be our primary goal. We should work to give all groups an equal chance to succeed. (reverse-scored) We should do what we can to equalize conditions for different groups. (reverse-scored) No matter how much effort it takes, we ought to strive to ensure that all groups have the same chance in life. (reverse-scored) Group equality should be our ideal. (reverse-scored)
SDO-6 items
Some groups of people are just more worthy than others. In getting what you want, it is sometimes necessary to use force against other groups. It's OK if some groups have more of a chance in life than others. To get ahead in life, it is sometimes necessary to step on other groups. If certain groups stayed in their place, we would have fewer problems. It's probably a good thing that certain groups are at the top and other groups are at the bottom. Inferior groups should stay in their place. Sometimes other groups must be kept in their place. It would be good if groups could be equal. (reverse-scored) Group equality should be our ideal. (reverse-scored) All groups should be given an equal chance in life. (reverse-scored) We should do what we can to equalize conditions for different groups. (reverse-scored) Increased social equality is beneficial to society. (reverse-scored) We would have fewer problems if we treated people more equally. (reverse-scored) We should strive to make incomes as equal as possible. (reverse-scored) No group should dominate in society. (reverse-scored)
Keying is reversed on questions 9 through 16, to control for acquiescence bias.
Criticisms of the construct Rubin and Hewstone (2004) argue that social dominance research has changed its focus dramatically over the years, and these changes have been reflected in different versions of the social dominance orientation construct. Social dominance orientation was originally defined as "the degree to which individuals desire social dominance and superiority for themselves and their primordial groups over other groups" (p. 209). It then quickly changed to not only "(a) a...desire for and value given to in-group dominance over out-groups" but also "(b) the desire for nonegalitarian, hierarchical relationships between groups within the social system" (p. 1007). The most recent measure of social dominance orientation (see SDO-6 above) focuses on the "general desire for unequal relations among social groups, regardless of whether this means ingroup domination or ingroup subordination" (p. 312). Given these changes, Rubin and Hewstone believe that evidence for social dominance theory should be considered "as supporting three separate SDO hypotheses, rather than one single theory" (p. 22).
Group-based and individual dominance
Robert Altemeyer said that people with a high SDO want more power (agreeing with items such as "Winning is not the first thing; it's the only thing"). These observations are at odds with conceptualisations of SDO as a group-based phenomenon, suggesting that the SDO reflects interpersonal dominance, not only group-based dominance. This is supported by Sidanius and Pratto's own evidence that high-SDO individuals tend to gravitate toward hierarchy-enhancing jobs and institutions, such as law enforcement, that are themselves hierarchically structured vis-a-vis individuals within them.
Relations with other personality traits
Connection with right-wing authoritarianism
SDO correlates weakly with right-wing authoritarianism (RWA) (r ≈ .18). Both predict attitudes, such as sexist, racist, and heterosexist attitudes. The two contribute to different forms of prejudice: SDO correlates to higher prejudice against subordinate and disadvantaged groups, RWA correlates to higher prejudice against groups deemed threatening to traditional norms, while both are associated with increases in prejudice for "dissident" groups. SDO and RWA contribute to prejudice in an additive rather than interactive way (the interaction of SDO and RWA accounted, in one study, for an average of less than .001% variance in addition to their linear combination), that is the association between SDO and prejudice is similar regardless of a person's level of RWA, and vice versa. Crawford et al. (2013) found that RWA and SDO differentially predicted interpretations of media reports about socially threatening (for example, gays and lesbians) and disadvantaged groups (for example, African Americans), respectively. Subjects with high SDO, but not RWA, scores reacted positively to articles and authors that opposed affirmative action, and negatively to pro-affirmative-action article content. Moreover, RWA, but not SDO, predicted subjects' evaluations of same-sex relationships, such that high-RWA individuals favored anti-same-sex relationships article content and low-RWA individuals favorably rated pro-same-sex relationships content.
Correlation with Big Five personality traits
Studies on the relationship of SDO with the higher order Big Five personality traits have associated high SDO with lower openness to experience and lower agreeableness. Meta-analytic aggregation of these studies indicates that the association with low Agreeableness is more robust than the link to Openness to experience. Individuals low in Agreeableness are more inclined to report being motivated by self-interest and self-indulgence. They also tend to be more self-centred and are more 'tough-minded' compared to those who are high on Agreeableness, leading them to perceive the world to be a highly competitive place, where the way to success is through power and dominance – all of which predict SDO.
Low Openness, by contrast, aligns more strongly with RWA; thinking in clear and straightforward moral codes that dictate how society as a system should function. Being low in Openness prompts the individual to value security, stability and control: fundamental elements of RWA.
Facet-level associations