Given that these judgments tend to remain stable, even as the length of interaction increases, they can influence important interpersonal outcomes.
The study of zero-acquaintance personality judgments developed from Cleeton and Knight's (1924)[1] intent to demonstrate the futility of using physical criteria to predict unobservable individual traits.
In order to accomplish this, Cleeton and Knight (1924)[1] recruited 30 target participants from national fraternities and sororities, so that a large group of close acquaintances from these organizations could rate eight traits (i.e. individual traits included sound judgment, intellectual capacity, frankness, willpower, ability to make friends, leadership, originality, and impulsiveness) of the target participants.
Passini and Norman (1966)[2] found comparable evidence that strangers provide similar ratings of unobservable personality traits of a target participant with no prior acquaintanceship.
Given that the strangers tended to rate a target participant's personality similarly, Passini and Norman (1966)[2] posited that some common observable characteristics must be informing these judgements.
These findings went unnoticed for over twenty years, until Albright, Kenny, and Malloy (1988)[4] revived interest and formally coined the term zero-acquaintance personality judgments.
These researchers established that certain physical appearance variables, including attractiveness, type of dress (both formal and neatness), and perceived age, informed strangers' zero-acquaintance personality judgments.
[6] This explanation posits that consensus arises when raters agree on the meaning of the information they use to make personality judgments.
Assuming perceivers hold this stereotype, they will make similar emotional stability ratings when the target's gender is known.
Because perceivers tend to agree on targets' physical attractiveness, consensus for extraversion is generally high.
Since extraversion largely measures social tendencies, it makes sense that the highest consensus and accuracy are found for this trait.
[10] This stark difference in validity suggests that agreeableness is much harder to judge with accuracy when the rater is unfamiliar with the target.
When raters are not very acquainted with the targets they are rating, it appears that the length of time they are actually able to observe the person doesn't have a strong influence on the accuracy of the behavioral judgments made.
[13] A later study examined this same topic over an extended period of time in order to better test an "acquaintance effect" on ratings.
Recent research employing zero-acquaintance situations has largely focused on what traits are judged most consistently and accurately, and in what contexts.
Interest in photographs has continued to increase in recent years, given the widespread use of these images on social media sites.
Specifically, perceivers were only able to accurately judge extraversion, self-esteem, and religiosity using a non-expressive full body photograph.
When the target struck a pose, however, the perceiver was able to judge extraversion, agreeableness, emotional stability, openness, likeability, self-esteem, loneliness, religiosity, and political orientation with some degree of accuracy.
In a more recent study exploring the accuracy of personality judgments in selfie profile pictures, Qiu, Lu, Yang, Qu, and Zhu (2015)[16] found that perceivers only accurately predict openness from selfies; these ratings were formed through impressions of the target's emotional positivity.
Gosling and colleagues (2002)[5] found that perceivers can more accurately rate targets' personality by observing their bedrooms than their offices.
When observing the bedrooms, perceivers could accurately rate extraversion, agreeableness, conscientiousness, emotional stability, and openness to experience.
More recently, Back et al. (2010)[8] investigated how well perceivers could make judgements of targets by viewing their social media profiles, either on Facebook or StudiVZ.
The researchers found that perceivers could accurately predict extraversion, agreeableness, conscientiousness, and openness of a target by simply perusing the social media profile.
Additionally, some sources of information (e.g. writing samples) portray culture and demographics to a lesser extent than others (e.g. photographs), which may lead to important differences in the judgments made.