In reporting Implicit Association Test (IAT) results, researchers have most often used scoring conventions described in the first publication of the IAT (A. G. Greenwald, D. E. McGhee, & J. L. K. Schwartz, 1998). Demonstration IATs available on the Internet have produced large data sets that were used in the current article to evaluate alternative scoring procedures. Candidate new algorithms were examined in terms of their (a) correlations with parallel self-report measures, (b) resistance to an artifact associated with speed of responding, (c) internal consistency, (d) sensitivity to known influences on IAT measures, and (e) resistance to known procedural influences. The best-performing measure incorporates data from the IAT's practice trials, uses a metric that is calibrated by each respondent's latency variability, and includes a latency penalty for errors. This new algorithm strongly outperforms the earlier (conventional) procedure.

Social behavior is ordinarily treated as being under conscious (if not always thoughtful) control. However, considerable evidence now supports the view that social behavior often operates in an implicit or unconscious fashion. The identifying feature of implicit cognition is that past experience influences judgment in a fashion not introspectively known by the actor. The present conclusionthat attitudes, self-esteem, and stereotypes have important implicit modes of operation-extends both the construct validity and predictive usefulness of these major theoretical constructs of social psychology. Methodologically, this review calls for increased use of indirect measures-which are imperative in studies of implicit cognition. The theorized ordinariness of implicit stereotyping is consistent with recent findings of discrimination by people who explicitly disavow prejudice. The finding that implicit cognitive effects are often reduced by focusing judges' attention on their judgment task provides a basis for evaluating applications (such as affirmative action) aimed at reducing such unintended discrimination.Long before they became central to other areas of psychological theory, concepts of cognitive mediation dominated the analysis of social behavior. The constructs on which this article focuses achieved early prominence in social psychological theory with formulations that were partly (attitude) or entirely (stereotype) cognitive. By the 1930s, Allport (1935) had declared attitude to be social psychology's "most distinctive and indispensable concept" (p. 798), Thurstone (1931;Thurstone & Chave, 1929) had developed quantitatively sophisticated methods for attitude measurement, and Braly (1933, 1935) had introduced a method that is still in use to investigate stereotypes. Self-esteem, an attitudinal construct to which this article gives separate treatment because of its prominence in recent research, also has a long-established history (e.g., James, 1890; see overview in Wylie, 1974Wylie, , 1979.Through much of the period since the 1930s, most social psychologists have assumed that attitudes, and to a lesser extent stereotypes, operate in a conscious mode. This widespread assumption of conscious operation is most evident in the nearuniversal practice of operationalizing attitudes (including selfesteem) and stereotypes with direct (instructed self-report) measures. The pervasiveness of direct measurement for attitudes and stereotypes was documented by Greenwald (1990) and by Banaji and Greenwald (1994) and is further reviewed below. In contrast, this article describes an indirect, unconscious, or implicit mode of operation for attitudes and stereotypes. 1 Anthony G. Greenwald, Department of Psychology, University of Washington; Mahzarin R. Banaji, Department of Psychology, Yale University.Preparation of this report as well as conduct of some of the research reported in it were supported by National Science Foundation Grants DBC-9205890 and DBC-9120987 and by National Institute of Mental Health Grant MH-41328. We thank...

Most theories in social and political psychology stress self-interest, intergroup conflict, ethnocentrism, homophily, ingroup bias, outgroup antipathy, dominance, and resistance. System justification theory is influenced by these perspectives-including social identity and social dominance theories-but it departs from them in several respects. Advocates of system justification theory argue that (a) there is a general ideological motive to justify the existing social order, (b) this motive is at least partially responsible for the internalization of inferiority among members of disadvantaged groups, (c) it is observed most readily at an implicit, nonconscious level of awareness and (d) paradoxically, it is sometimes strongest among those who are most harmed by the status quo. This article reviews and integrates 10 years of research on 20 hypotheses derived from a system justification perspective, focusing on the phenomenon of implicit outgroup favoritism among members of disadvantaged groups (including African Americans, the elderly, and gays/lesbians) and its relation to political ideology (especially liberalism-conservatism).KEY WORDS: ideology, system justification, intergroup relations, implicit bias There is a cluster of related theories that are by now so prevalent in social science that they strike the contemporary reader as self-evidently true. Although these theories are by no means indistinguishable, they share a set of common features, including the tenets that groups serve their own interests, develop ideolo-

This review of 122 research reports (184 independent samples, 14,900 subjects) found average r = .274 for prediction of behavioral, judgment, and physiological measures by Implicit Association Test (IAT) measures. Parallel explicit (i.e., self-report) measures, available in 156 of these samples (13,068 subjects), also predicted effectively (average r = .361), but with much greater variability of effect size. Predictive validity of self-report was impaired for socially sensitive topics, for which impression management may distort self-report responses. For 32 samples with criterion measures involving Black-White interracial behavior, predictive validity of IAT measures significantly exceeded that of self-report measures. Both IAT and self-report measures displayed incremental validity, with each measure predicting criterion variance beyond that predicted by the other. The more highly IAT and self-report measures were intercorrelated, the greater was the predictive validity of each.

Although the concept of justification has played a significant role in many social psychological theories, its presence in recent examinations of stereotyping has been minimal. We describe and evaluate previous notions of stereotyping as ego‐justification and group‐justification and propose an additional account, that of system‐justification, which refers to psychological processes contributing to the preservation of existing social arrangements even at the expense of personal and group interest. It is argued that the notion of system‐justification is necessary to account for previously unexplained phenomena, most notably the participation by disadvantaged individuals and groups in negative stereotypes of themselves, and the consensual nature of stereotypic beliefs despite differences in social relations within and between social groups. We offer a selective review of existing research that demonstrates the role of stereotypes in the production of false consciousness and develop the implications of a system‐justification approach. [T]he rationalizing and justifying function of a stereotype exceeds its function as a reflector of group attributes—G. W. Allport (1958, p. 192).

This theoretical integration of social psychology's main cognitive and affective constructs was shaped by 3 influences: (a) recent widespread interest in automatic and implicit cognition, (b) development of the Implicit Association Test (IAT; A. G. Greenwald, D. E. McGhee, & J. L. K. Schwartz, 1998), and (c) social psychology's consistency theories of the 1950s, especially F. Heider's (1958) balance theory.The balanced identity design is introduced as a method to test correlational predictions of the theory. Data obtained with this method revealed that predicted consistency patterns were strongly apparent in the data for implicit (IAT) measures but not in those for parallel explicit (self-report) measures. Two additional not-yet-tested predictions of the theory are described.

Six studies investigated the extent to which American ethnic groups (African, Asian, and White) are associated with the category "American." Although strong explicit commitments to egalitarian principles were expressed in Study 1, Studies 2-6 consistently revealed that both African and Asian Americans as groups are less associated with the national category "American" than are White Americans. Under some circumstances, a dissociation between mean levels of explicit beliefs and implicit responses emerged such that an ethnic minority was explicitly regarded to be more American than were White Americans, but implicit measures showed the reverse pattern (Studies 3 and 4). In addition, Asian American participants themselves showed the American = White effect, although African Americans did not (Study 5). The American = White association was positively correlated with the strength of national identity in White Americans. Together, these studies provide evidence that to be American is implicitly synonymous with being White.

CONTEXT: Studies documenting racial/ethnic disparities in health care frequently implicate physicians' unconscious biases. No study to date has measured physicians' unconscious racial bias to test whether this predicts physicians' clinical decisions. OBJECTIVE:To test whether physicians show implicit race bias and whether the magnitude of such bias predicts thrombolysis recommendations for black and white patients with acute coronary syndromes. DESIGN, SETTING, AND PARTICIPANTS:An internetbased tool comprising a clinical vignette of a patient presenting to the emergency department with an acute coronary syndrome, followed by a questionnaire and three Implicit Association Tests (IATs). Study invitations were e-mailed to all internal medicine and emergency medicine residents at four academic medical centers in Atlanta and Boston; 287 completed the study, met inclusion criteria, and were randomized to either a black or white vignette patient.MAIN OUTCOME MEASURES: IAT scores (normal continuous variable) measuring physicians' implicit race preference and perceptions of cooperativeness. Physicians' attribution of symptoms to coronary artery disease for vignette patients with randomly assigned race, and their decisions about thrombolysis. Assessment of physicians' explicit racial biases by questionnaire. RESULTS:Physicians reported no explicit preference for white versus black patients or differences in perceived cooperativeness. In contrast, IATs revealed implicit preference favoring white Americans (mean IAT score=0.36, P<.001, one-sample t test) and implicit stereotypes of black Americans as less cooperative with medical procedures (mean IAT score 0.22, P<.001), and less cooperative generally (mean IAT score 0.30, P<.001). As physicians' prowhite implicit bias increased, so did their likelihood of treating white patients and not treating black patients with thrombolysis (P=.009).CONCLUSIONS: This study represents the first evidence of unconscious (implicit) race bias among physicians, its dissociation from conscious (explicit) bias, and its predictive validity. Results suggest that physicians' unconscious biases may contribute to racial/ ethnic disparities in use of medical procedures such as thrombolysis for myocardial infarction.