Fooled by first impressions? Reexamining the diagnostic value of appearance-based inferences

We often form opinions about the characteristics of others from single, static samples of their appearance – the very first thing we see when, or even before, we meet them. These inferences occur spontaneously, rapidly, and can impact decisions in a variety of important domains. A crucial question, then, is whether appearance-based inferences are accurate. Using a naturalistic data set of more than 1 million appearance-based judgments obtained from a popular website (Study 1) and data from an online experiment involving over a thousand participants (Study 2), we evaluate the ability of human judges to infer the characteristics of others from their appearances. We find that judges are generally less accurate at predicting characteristics than they would be if they ignored appearance cues and instead only relied on their knowledge of characteristic base-rate frequencies. The findings suggest that appearances are overweighed in judgments and can have detrimental effects on accuracy. We conclude that future research should (i) identify the specific visual cues that people use when they draw inferences from appearances, (ii) determine which of these cues promote or hinder accurate social judgments, and (iii) examine how inference goals and contexts moderate the use and diagnostic validity of these cues. 2009 Elsevier Inc. All rights reserved. & Stewart, 2009; Zebrowitz & McDonald, 1991), and the military ‘‘Beware, as long as you live, of judging people by appearances.” – The Cockerel, the Cat, and the Young Mouse (Jean de La Fontaine, 1668/1974). Despite the old adage warning us not to ‘‘judge a book by its cover,” we often form opinions about the characteristics of others from single, static samples of their appearance – the very first thing we see when, or even before, we meet them (Hassin & Trope, 2000; Todorov, Said, Engell, & Oosterhof, 2008; Zebrowitz, 1996). These inferences occur spontaneously and rapidly (Ballew & Todorov, 2007; Bar, Neta, & Linz, 2006; Rule & Ambady, 2008a; Todorov, Pakrashi, & Oosterhof, 2009; Willis & Todorov, 2006). Furthermore, recent evidence suggests that these impressions impact the decisions that people make in a variety of important domains, including mate choice (Olivola et al., 2009), politics (for reviews of this literature see: Hall, Goren, Chaiken, & Todorov, 2009; Olivola & Todorov, in press), business/finance (Gorn, Jiang, & Johar, 2008; Naylor, 2007; Pope & Sydnor, 2008; Ravina, 2008; Rule & Ambady, 2008b), law/forensic-science (Blair, Judd, & Chapleau, 2004; Eberhardt, Davies, Purdie-Vaughns, & Johnson, 2006; Zarkadi, Wade, ll rights reserved. eptual and Brain Sciences, WC1H 0AP, United Kingdom. (Mueller & Mazur, 1996). A crucial question, then, is whether appearance-based inferences are valid forms of social judgment. That is, can we use appearances to determine a target-person’s characteristics, or are we being fooled by first impressions? The answer to this question has serious and wide-ranging implications. The widespread use of visual media and the growing popularity of the Internet mean that appearances are increasingly the first cues we receive about another person (e.g., through posted photos), often long before we meet them. While previous studies have examined the diagnostic validity of appearances, the resulting evidence has been mixed (Ambady, Hallahan, & Conner, 1999; Hassin & Trope, 2000; Rule & Ambady, 2008a; Zebrowitz & Collins, 1997; Zebrowitz & Montepare, 2008). Furthermore, in many of these studies, the distributions of target characteristics were manipulated to be equiprobable, and thus did not reflect actual category membership frequencies in the real world. This feature, in particular, may have led to premature and overly optimistic conclusions regarding the diagnostic value of appearances in everyday social judgments – a point that we return to in the discussion. The goal of this paper is to critically explore the validity of appearance-based judgments by examining what happens when one can draw on both appearances and category-frequency infor1 By ‘‘perceptually ambiguous characteristics”, we mean characteristics that cannot be easily inferredfrom a person’s photo, as opposed to ethnicity or gender, for example,which are often easy to judge from appearance. And by ‘‘clear categories”, we mean those forming discrete subgroups that people can classify themselves into with high confidence, as opposed to variables without clear boundaries or for which people may not be able to reliably classify themselves (e.g., number of hours spent working per week). 316 C.Y. Olivola, A. Todorov / Journal of Experimental Social Psychology 46 (2010) 315–324 mation to infer something about another person. A competent judge with access to both pieces of information should weigh each cue in proportion to its validity and thus perform (on average) as well as or better than she would if she only had access to one of them. If, however, we tend to allocate too much weight to appearances, then the availability of photos and other static social-visual cues may actually hinder our ability to form accurate social judgments about characteristics with highly predominant categories. In this case, reliance on appearances could be detrimental to judgment accuracy, even when appearance-based inferences are ‘‘accurate” in the sense that they exceed chance. To explore this possibility, we conducted two studies in which we measured people’s judgment accuracy-levels as they tried to guess others’ characteristics using photos of the targets and information about the underlying category-frequencies. In Study 1, we compare performance across a variety of characteristics that differ naturally in terms of their category-frequency distributions. In Study 2, we focus on a single characteristic but experimentally vary its categoryfrequencies to see how this impacts performance.