Individuals make judgments of others everyday — sometimes on the basis of very little information or interaction with the person they are judging.  These judgments can have considerable influence on social outcomes.  The good news is, recent research has shown that people can make fairly accurate judgments of others after minimal interactions with them or more surprisingly, after only seeing them in photographs or video clips.  A situation in which perceivers make judgments about targets they are given no opportunity to interact with is called zero acquaintance.  In zero-acquaintance studies, the perceiver and the target are strangers.  Further, because they have not interacted prior to the judgment, any perception is attributed primarily to the physical features of the target.

The least acquaintance between two persons, besides ESP, is zero acquaintance.  It is the condition in which a perceiver observes a target, but the perceiver does not interact with the target. Moreover, the target is not engaged in social interaction.  For instance, you are at a restaurant and you see someone on that restaurant sitting alone and you try to imagine that person's personality.

The first major study of zero acquaintance that I know of was published by Warren Norman and Lou Goldberg in 1966. They had University of Michigan students rate each other's personality on the first day of class.  The study yielded two sets of very surprising results. First, students agreed with one another about each other's personality.  Second, and even more surprisingly, these ratings by virtual strangers agreed with the targets' self-ratings.  So if two people agreed that a third person was friendly, that person tended to see him or herself as friendly. Thus, these judgments at zero acquaintance are consensual and appear to be valid.

Perhaps because of its counter-intuitive nature, these findings demonstrated by Norman and Goldberg study were virtually totally ignored.  In 1988 at the University of Connecticut, Linda Albright, Thomas Malloy, and myself published three studies of zero acquaintance using the paradigm that Norman and Goldberg developed.  (You can download the three raw data sets from this study: MALZER, KENZER, and ZERO.)  We had students on the first day of class form a circle and rate each other. We replicated the results of Norman and Goldberg.  Across three separate studies with 259 participants, there was consensus on the dimensions of Extroversion and Conscientiousness and correlations between perceiver judgments with and self-ratings; we, however, used a more elaborate statistical model (the Social Relations Model).

After the publication of the Albright, Malloy, and Kenny study, there have been numerous follow-up studies, done at the University of Connecticut and around the world.  Each of these studies shows evidence of agreement in ratings and correlations with self-ratings. In Kenny, Horner, Kashy, and Chu (1992), we studied zero acquaintance in more controlled settings.  Participants viewed 20 sec. video clips in a laboratory setting. We were able to replicate the basic results of consensus being highest for judgments of Extroversion and somewhat weaker for Conscientiousness.

Several important studies were conducted by Peter Borkenau and Annette Liebler (1992,  1993) in Germany.  They undertook special measures to ensure that the targets and judges are unacquainted. Additionally, they used a community sample of targets, not just college students as have been used in other studies. Borkenau and Liebler find even stronger levels of agreement or consensus, likely because a community sample would be more heterogeneous than a sample of college students. They also consistently found evidence of correlations between zero-acquaintance ratings and self-ratings.

Maurice Levesque and myself (1993) examined more closely the finding that perceivers generally agree about who is and is not extroverted and included a behavioral measure of accuracy.  Participants formed groups of unacquainted women and without interacting each woman rated the other group members on traits indicating the Big 5 factors and made a series of behavioral predictions (e.g., talkativeness).  We found that not only was there consensus on rating of talkativeness but when the women were videotaped interacting one-on-one with each other women who were judged as more talkative actually talked more.

Other investigators (David Watson, Brett Pelham and William Swann, and Marina DiPilato) have replicated the basic zero-acquaintance results. Furthermore, investigators have used photographs and obtained similar results (Ronald Henss).  Leslie Zebrowitz of Brandeis University in her book, entitled Reading Faces: Window to the Soul?, reviewed many of these studies.  Nalini Ambady, Mark Hallahan, and Robert Rosenthal (1995) examined moderators of accuracy in the zero acquaintance paradigm.

To my knowledge, only one published zero-acquaintance study involved non-western subjects (Albright, Malloy, Dong, Kenny, Fang, Winquist, and Yu, 1997).  This study was conducted at Beijing Normal University in China. Although some results were somewhat different, they were basically consistent with results from studies of persons from western cultures: Perceivers agree in their ratings at zero acquaintance and these rating correlate with self-ratings.

Research has consistently shown that agreement at zero acquaintance is strongest for Extroversion. Remember that people know how talkative someone is, even if they have never seen the person engage in conversation. Agreement is generally shown for ratings of Conscientiousness. Agreement for Agreeableness, Emotional Stability, and Culture tend to be less. As for validity, it seems to be greatest for Conscientiousness. Recall, however, that Borkenau and Liebler find even stronger levels of agreement and validity with a community sample.

Although correlations of ratings at zero acquaintance with self-ratings suggest that the zero-acquaintance ratings are valid, there are alternative explanations. For instance, it might be that a person successfully conveys a false image through clothing and speech. For instance, someone who falsely thinks he or she is athletic wears athletic clothing and perceivers mistakenly conclude that the person is athletic. Stronger evidence that zero-acquaintance ratings are accurate is needed.

The Levesque and Kenny 1993 study done at the University of Connecticut provides to date the strongest foundation of validity.  Zero-acquaintance ratings of Extroversion predicted how much each woman talked and how much each gestured. Many of these correlations were very strong. Work by Nalini Ambady and Robert Rosenthal of Harvard University on what they call thin slices supports the validity of zero-acquaintance ratings. There is increasing evidence that consensual judgments based on limited information are surprisingly valid.

 
For there to be consensus at zero acquaintance, there must be shared beliefs about links between either physical appearance or nonverbal behavior with personality.  Shared beliefs about persons are called stereotypes in social psychology.  We do know that the stereotypes used at zero acquaintance are not primarily based on either gender, ethnicity, or social class. Appearance cues and nonverbal behaviors are associated with different personality traits. For instance, at least in western cultures, physical attractiveness is associated with judgments of extroversion whereas in China physical attractiveness is associated with judgments of intelligence.

Borkenau and Liebler, following the pioneering work of Robert Gifford, have done the most detailed investigation of cues used to make personality judgments at zero acquaintance. For instance, they have shown that vocal cues are important for judging Agreeableness. They find that there are many cues for judgments of Extroversion.

A common metaphor in person perception, taken from Altman and Taylor, is that perceivers must peel away the layers of onion, before seeing what the target is really like. These zero-acquaintance results suggest a rethinking of the role of acquaintance in person perception. We learn about others' personalities in seconds. Thus, there can be accuracy of perception very early.

Research has shown that increased acquaintance generally increases the validity of person perceptions. Thus, it would be a mistake to rely on the perceptions at zero acquaintance. However, the increase in accuracy due to acquaintance is much quicker than might be thought (see target accuracy page) and the level of accuracy for people well-acquainted with the target is not as great as might be thought. Thus, if we were to chart the relationship between accuracy and acquaintance, perceivers begin higher and finish at lower level of accuracy than might be thought.

Sam Gosling, Sei Jin Ko, Thomas Mannarelli, and Margaret Morris (2002) had individuals make judgments about a target after seeing the targets office or bedroom.  They showed that strangers could reliable and validly judge targets’ personalities by looking at their bedrooms and offices.  Consensus and accuracy correlations were generally stronger than those found in zero-acquaintance research.  This study demonstrates that accuracy is possible without ever meeting (or even seeing) a person.

Nalini Ambady, Mark Hallahan, and Brett Connor (1998) have demonstrated consensus and better than chance accuracy at judging sexual orientation on the basis of 10 second and 1 second video clips, still photographs, and even a 10 second figural outline display.   Evidence suggests that gay men and lesbians are more accurate than heterosexuals at judging sexual orientation in some conditions (still photographs and 1 second clips) but not others (10 second clips).

Jason Themason of the University of Connecticut, has investigated gender differences in the perception of physical attractiveness at zero-acquaintance.  He has found minimal differences.  However, work by David Marcus and Rowland Miller of Sam Houston University have found differences.

Jo Korchmaros and I have completed two studies asking people to make predictions who would be helpful and who would the person be willing to help.  We find consensus on both variables but mixed results in terms of accuracy.

Albright, L., Kenny, D. A., & Malloy, T. E. (1988). Consensus in personality judgments at zero acquaintance. Journal of Personality and Social Psychology, 55, 387-395.

Albright, L., Malloy, T. E., Dong, Q., Kenny, D. A., Fang, X., Winquist, L., & Yu, D. (1997). Cross-cultural consensus in personality judgments. Journal of Personality and Social Psychology, 72, 558-569.

Ambady, N., Hallahan, M., & Conner, B. (1999). Accuracy of judgments of sexual orientation from thin slices of behavior. Journal of Personality and Social Psychology, 77, 538-547.

Ambady, N., Hallahan, M., & Rosenthal, R. (1995).  On judging and being judged accurately in zero-acquaintance situations.  Journal of Personality and Social Psychology, 69, 518-529.

Altman, I., & Taylor, D. A. (1973). Social penetration. New York: Holt.

Ambady, N., & Rosenthal, R. (1992). Thin slices of expressive behavior as predictors of interpersonal consequences: A meta-analysis. Psychological Bulletin, 111, 256-274.

Borkenau, P. & Liebler, A. (1992). Trait inferences: Sources of validity at zero acquaintance.  Journal of Personality and Social Psychology, 62, 645-657.

Borkenau, P. & Liebler, A. (1993). Convergence of stranger ratings of personality and intelligence with self-ratings, partner ratings, and measured intelligence. Journal of Personality and Social Psychology, 65, 546-553.

DiPilato, M. (1989). Person perception in initial acquaintance: Changes over time and task-trait match. Doctoral dissertation. Arizona State University.

Gifford, R. (1991). Mapping nonverbal behavior on the interpersonal circle. Journal of Personality and Social Psychology, 61, 279-288.

Gosling, S., Ko, S. J., Mannarelli, R., & Morris, M. E. (2002).  A room with a cue: Personality judgments based on offices and bedrooms.  Journal of Personality and Social Psychology, 82, 379-398.

Kenny, D. A., Horner, C., Kashy, D. A., & Chu, L. (1992). Consensus at zero acquaintance: Replication, behavioral cues, and stability. Journal of Personality and Social Psychology, 62, 88-97.

Levesque, M. J., & Kenny, D. A. (1993). Accuracy of behavioral predictions at zero acquaintance: A social relations analysis. Journal of Personality and Social Psychology, 65, 1178-1187.

Norman, W. T., & Goldberg, L. R. (1966). Raters, ratees, and randomness in personality structure. Journal of Personality and Social Psychology, 4, 681-691.

Pelham, B. W., & Swann, W. B., Jr. (1994). The juncture of intrapersonal and interpersonal knowledge: Self-certainty and interpersonal congruence. Personality and Social Psychology Bulletin, 20, 349-357.

Watson, D. (1989). Strangers' ratings of the five robust personality factors: Evidence of surprising convergence with self-report. Journal of Personality and Social Psychology, 57, 120-128.