Monday, May 2, 2022

Can people detect the trustworthiness of strangers based on their facial appearance? It seems not.

Can people detect the trustworthiness of strangers based on their facial appearance? Bastian Jaeger et al. Evolution and Human Behavior, May 2 2022.

Abstract: Although cooperation can lead to mutually beneficial outcomes, cooperative actions only pay off for the individual if others can be trusted to cooperate as well. Identifying trustworthy interaction partners is therefore a central challenge in human social life. How do people navigate this challenge? Prior work suggests that people rely on facial appearance to judge the trustworthiness of strangers. However, the question of whether these judgments are actually accurate remains debated. The present research examines accuracy in trustworthiness detection from faces and three moderators proposed by previous research. We investigate whether people show above-chance accuracy (a) when they make trust decisions and when they provide explicit trustworthiness ratings, (b) when judging male and female counterparts, and (c) when rating cropped images (with non-facial features removed) and uncropped images. Two studies showed that incentivized trust decisions (Study 1, n = 131 university students) and incentivized trustworthiness predictions (Study 2, n = 266 university students) were unrelated to the actual trustworthiness of counterparts. Accuracy was not moderated by stimulus type (cropped vs. uncropped faces) or counterparts' gender. Overall, these findings suggest that people are unable to detect the trustworthiness of strangers based on their facial appearance, when this is the only information available to them.

Keywords: TrustTrustworthinessCooperationFace perceptionPredictionAccuracy

4. General discussion

People spontaneously rely on the facial appearance of strangers when deciding whether they can be trusted to cooperate in social interactions (Todorov, Olivola, et al., 2015). But can people actually detect the trustworthiness of strangers based on their facial appearance? Prior studies have yielded mixed results and the question remains the subject of vigorous debate (Bonnefon et al., 2017Todorov, Funk, & Olivola, 2015). Yet, the empirical evidence on the topic is limited. Many studies were based on the same set of stimuli, which limits the generalizability of findings (Bonnefon et al., 2013De Neys, Hopfensitz and Bonnefon, 2015De Neys, Hopfensitz and Bonnefon, 2017). Conversely, studies providing evidence against accuracy relied on statistical techniques that cannot quantify evidence in favor of such a null hypothesis, which complicates the interpretation of results (Efferson & Vogt, 2013Rule et al., 2013).

We conducted two studies to address these limitations. Confirming results from previous studies (Jaeger, Evans, Stel, & van Beest, 2019), we found that participants relied on the perceived trustworthiness of counterparts when making trust decisions. However, on average, participants failed to entrust money to counterparts that were actually more trustworthy. Bayesian analyses yielded very strong support for the null hypothesis indicating that our participants were not able to accurately detect the trustworthiness of their interaction partners. We also found that participants' earnings were not higher than the expected earnings of a decision strategy that trusts at random. This suggests that knowledge of their counterparts' facial appearance did not give participants a strategic advantage. In fact, participants would have earned more by consistently distrusting all counterparts, as trust did not pay off in the current sample.

Previous studies found evidence in favor of detection accuracy only under specific conditions, and these conditions varied across studies (Bonnefon et al., 2013Tognetti et al., 2013Verplaetse et al., 2007). Here, we tested these proposed moderators, but found no evidence for better-than-chance trustworthiness detection (a) for male or female counterparts, (b) when making trust decisions or when providing explicit trustworthiness ratings, and (c) when viewing cropped images (in which all non-facial features were removed) or uncropped images. In sum, our results provide consistent evidence against accuracy in trustworthiness detection from faces across various conditions.

Previous investigations have shown that trustworthiness impressions guide decision-making in many domains, including legal sentencing, personnel selection, and financial decision-making (Olivola et al., 2014). People even rely on trustworthiness impressions from faces when more diagnostic cues are available (Jaeger et al., 2019) and when decisions are highly consequential (Wilson & Rule, 2015). Future studies should explore whether some people are more prone to the biasing influence of first impressions and, importantly how biases could be mitigated (for first attempts, see Chua & Freeman, 2021Jaeger, Todorov, Evans, & van Beest, 2020Shen & Ferguson, 2021). An important future task in this line of research will be to delineate how difficult it is to override these biases, particularly when other more reliable information sources are available that may require more cognitive effort to process.

4.1. Limitations and future directions

Several limitations and constraints on the generalizability of the current results should be mentioned. Our results were based on samples of relatively young decision-makers from the University of Zurich. Additional studies are needed to examine the generalizability of our findings with larger and more diverse samples of both targets and raters.

Future studies should also examine the accuracy of trustworthiness impressions using varying types of stimuli. Cropped images, in which all non-facial aspects are removed, ensure that impressions are based on the facial features of counterparts. However, they represent only a relatively specific facet of the kinds of stimuli that people encounter in everyday interpersonal interactions. Accuracy may be better than chance when people have access to additional cues. For instance, previous findings suggest that people may be able to identify cooperative interaction partners with greater-than-chance accuracy after brief interactions (Brosig, 2002DeSteno et al., 2012Frank, Gilovich, & Regan, 1993Reed, Zeglen, & Schmidt, 2012; but see Manson, Gervais, & Kline, 2013McCullough & Reed, 2016). Ultimately, we believe that studies using a wide range of different stimuli are needed to map the accuracy of trustworthiness decisions under varying conditions.

We investigate one such condition here, namely the accuracy of trustworthiness judgments when judgments are solely based on facial features. This approach is informative for two reasons. First, even though people often have access to other cues, which may allow them to make more accurate judgments, there are also many situations in which a person's facial appearance is either one of the only cues or a particularly salient cue. People often engage with strangers and, in the first moments of the interaction, tend to judge them solely based on their appearance. Moreover, facial photographs are a common feature of many decision-making environments, including social media platforms (e.g., Twitter), professional networking sites (e.g., LinkedIn), and the sharing economy (e.g., Airbnb). Second, ample evidence suggests that people rely on facial appearance, even when they have access to other cues (Jaeger et al., 2019Olivola et al., 2014). To determine whether reliance on facial appearance helps or hinders people in making accurate predictions, the accuracy of judgments that are solely based on facial appearance needs to be isolated. This requires a highly controlled and standardized study design, such as the one used in the current experiments, to ensure that judgments are based on the cue in question (Cox et al., 2015).

At Harvard, the admit rates for typical African American applicants are on average over four times larger than if they had been treated as white; for typical Hispanic applicants the increase is 2.4 times

What the Students for Fair Admissions Cases Reveal About Racial Preferences. Peter Arcidiacono, Josh Kinsler & Tyler Ransom. NBER Working Paper 29964. Apr 2022. DOI 10.3386/w29964

Abstract: Using detailed admissions data made public in the SFFA v. Harvard and SFFA v. UNC cases, we examine how racial preferences for under-represented minorities (URMs) affect their admissions to Harvard and UNC-Chapel Hill. At Harvard, the admit rates for typical African American applicants are on average over four times larger than if they had been treated as white. For typical Hispanic applicants the increase is 2.4 times. At UNC, preferences vary substantially by whether the applicant is in-state or out-of-state. For in-state applicants, racial preferences result in an over 70% increase in the African American admit rate. For out-of-state applicants, the increase is more than tenfold. Both universities provide larger racial preferences to URMs from higher socioeconomic backgrounds.

Both genders applied self-deprecating double standards when viewing overweight and average-weight bodies; women, but not men, also showed self-deprecating double standards when viewing the ideal body and their own body

Giving a Body a Different Face—How Men and Women Evaluate Their Own Body vs. That of Others. Mona M. Voges, Hannah L. Quittkat, Benjamin Schöne and Silja Vocks. Front. Psychol., May 2 2022 |

Abstract: Eating disorders affect women more than men. Women reportedly dislike their body shape more and appreciate it less than do men. One factor influencing body image might be the application of different standards for oneself than for other people when evaluating bodies. To investigate this possibility, we determined whether the application of double standards is different between men and women. We presented 57 women and 54 men (aged 18–30 and of average weight) with pictures of their own bodies and pictures of average weight, overweight, and “ideal” bodies attached to the participants’ own face and to another person’s face. Participants were instructed to evaluate their emotional reaction to the pictures and then rate the various pictures on aspects of attractiveness, body fat, and muscle mass. The degree of the double standard was defined as the difference between ratings of what appeared to be one’s own body and what appeared to be someone else’s according to the presented face. The analyses revealed, firstly, that both genders applied self-deprecating double standards when viewing overweight and average-weight bodies. Women, but not men, also showed self-deprecating double standards when viewing the ideal body and their own body. By contrast, men applied fewer double standards when viewing the ideal body and self-enhancing double standards when viewing their own body. The study suggests that young, average-weight men are more or less satisfied with their own bodies, whereas young, average-weight women tend to apply a stricter standard for themselves than for others, thus devaluing their own bodies. This vulnerability to body image is hypothesized as contributing to the prevalence of eating disorders in women.


The present study was conducted to examine whether women differ from men in the application of double standards in body evaluation. Therefore, we presented the participants’ own bodies and average-weight, overweight, and ideal bodies, once with another face and once with the participant’s face. Women and men were asked to evaluate their emotional reaction regarding valence and arousal and to rate the bodies with regard to body attractiveness, body fat, and muscle mass. Double standard application was measured by the difference between the body ratings generated by the different faces.

First, our hypothesis that women and men would apply self-deprecating double standards in the case of an overweight body was confirmed. For both genders, self-deprecating double standards were observed on all dependent variables. Women and men rated their emotional reaction to an overweight body as more negative and with more arousal. They also rated the overweight body as less attractive, with more body fat, and with less muscle mass when the body had their own face compared to another person’s face. The double standards in valence, arousal, and body fat in the case of the overweight body were more self-deprecating than the double standards in valence, arousal, and body fat for the other body builds. These findings are in line with a previous study that employed cartoon-like body stimuli (Voges et al., 2019b) and might be related to negative stereotypes and stigma associated with overweight and obesity in Western society, e.g., obese people are often stigmatized as “careless,” “disorganized,” and “lazy” (Hu et al., 2018). The activation of self-related schemas through the presentation of one’s own face might result in stricter body evaluations, representing the participants’ rejection of overweight for their own bodies (Voges et al., 2019a).

Contrary to our hypothesis, women also showed self-deprecating double standards for other body builds—average-weight, ideal, and one’s own body—which is not in line with the findings of a previous study using cartoon-like body stimuli, which reported that women applied the same standard to the other images (Voges et al., 2019a). In contrast to the use of cartoon-like bodies in previous studies, participants in the present study evaluated real body stimuli (Voges et al., 2019b). This might have led to a better identification with the body stimuli and might have reinforced body schema activation, resulting in more pronounced double standards in women. Furthermore, as the present study also included women with a BMI of 25–30 kg/m2, the women had a higher average BMI than those in the aforementioned study, and they had higher body dissatisfaction and eating pathology than the sample in the previous study (Voges et al., 2019a). However, most women in the present sample (about 87%) had an average weight according to the WHO criteria, and the average BMI of 21.78 was, as in the previous study, in the lower-average weight category. Furthermore, body dissatisfaction and eating pathology were at an average and not notably different level compared to norms for young women (Paul and Thiel, 2005Mond et al., 2006). Thus, the present results suggest that not only women with eating disorders, but also women without eating disorders, might apply stricter standards for themselves than for others regarding body evaluation, which might foster body dissatisfaction.

The hypothesis that men would show self-enhancing double standards in the case of an ideal body and one’s own body can be partially confirmed by the present findings. With the exception of a self-deprecating double standard in body attractiveness, men showed no double standards for the ideal body, which is not in line with previous findings with artificially created bodies (Voges et al., 2019b). However, in the case of one’s own body, men showed self-enhancing double standards in valence and body attractiveness and no self-deprecating double standards. Although men evaluated the ideal body as more attractive than their own body, identification with this body did not lead to self-enhancing double standards. Thus, young men might have internalized the idea that their own body “fits them well” and does not need to correspond to existing male body ideals in society. This would be in line with findings that men do not believe that the ideal male body is more attainable for themselves than for other men, as women do in the case of the female ideal (Buote et al., 2011). Moreover, this idea would further be consistent with the examined correlations of body appreciation and body dissatisfaction with the self-enhancing double standards in men.

Comparing women’s and men’s body evaluations, women rated in a more self-deprecating manner than did men and, in contrast to men, did not show a self-enhancing double standard for one’s own body. Possibly, female and male stereotypes might contribute to such gender differences in body evaluation (Voges et al., 2019b). According to stereotypes concerning male and female characteristics, men should be “independent,” “strong,” and “outstanding,” while women should be “agreeable” and “friendly” (Guimond et al., 2006). Such stereotypes might simplify self-enhancing evaluation patterns in men while hampering them in women (Meyers-Levy and Loken, 2015). In line with this, men engage more in positive body talk than women (Lin et al., 2021), for whom it seems to be normative to engage in negative fat talk, i.e., degrading the body shape and weight of oneself or others (Tompkins et al., 2009). Thus, women might internalize a devaluation of their own body, while men might be more predisposed to upvalue their own body.

To check whether double standards are associated with body dissatisfaction and body appreciation, we conducted correlation analyses. In line with our hypotheses, the results revealed some associations of body dissatisfaction and body appreciation with double standards in women and men. For women, the higher the body dissatisfaction and the lower the body appreciation, the more self-deprecating was the double standard in valence for one’s own body. Furthermore, the higher the body dissatisfaction, the more self-deprecating were the double standards in arousal and body fat for one’s own body and the double standard in body fat for the overweight body. For men, the higher the body dissatisfaction, the less self-enhancing were the double standards in arousal, body attractiveness, and body fat for one’s own body. Furthermore, as mentioned above, the higher the body appreciation, the more self-enhancing were the double standards in valence and body attractiveness for one’s own body. These findings suggest that double standards related to one’s own body are more directly linked to body dissatisfaction and body appreciation than double standards related to other bodies, as most correlations were found for double standards related to one’s own body and not to the other bodies. This corresponds to the notion that the visual representation of one’s own body is influenced by the attitudes toward one’s own body (Williamson et al., 2004Maister et al., 2020) and that eating pathology is not linked to a generally distorted body perception or cognition but rather to a cognitive–affective distortion in evaluating one’s own body (Behrens et al., 2021). Thus, in addition to stricter standards for oneself, especially in body fat (Voges et al., 2018), eating pathology might be linked to a negative attitude toward one’s own body. With its idiosyncratic characteristics, one’s own body may not match one’s own standard, but may be viewed as more appropriate for other people.

Furthermore, for women, the association with double standards for the overweight body suggests that a stricter disapproval of overweight and obesity for oneself might also foster body dissatisfaction in average-weight women. The fact that no further associations of body dissatisfaction and body appreciation with double standards related to the other bodies (ideal, average-weight, overweight) were observed might also be partially explained by different cognitive reactions to these bodies leading to the same double standard. For example, self-deprecating double standards might emerge in persons with high body dissatisfaction because they generally devalue themselves compared to others and in persons with low body dissatisfaction, because they dislike imagining having the other body, and prefer their own body. Thus, in contrast to the double standards related to one’s own body, the associations between body dissatisfaction or body appreciation and the double standards related to the other bodies might not be so clear.

The present study is the first to examine double standards in body evaluation with photos of bodies including one’s own body and manipulating identification using different faces. By giving a body a different face, we were able to show that identity influences body evaluation differently in women and men. However, some limitations that might restrict the generalizability of the findings should be mentioned. Although the body stimuli were more realistic than those used in a previous study (Voges et al., 2019b), the stimulus material was standardized and gray-scaled, which likely limited the ecological validity. Furthermore, as we used photos of real persons, the bodies naturally differed somewhat in features other than body build (e.g., body height, skin features, body shape). However, for most body build categories, women and men rated the male and female bodies as equally attractive. As we did not assess persons with eating disorders, muscle dysmorphia, or severe body concerns, our results cannot be transferred to these clinical populations. Furthermore, as our study included a photo shoot in which participants wore their underwear, and participants were required to look at photos of their own body, women and men with high body dissatisfaction might have felt too daunted to participate. Based on previous findings with cartoon-like bodies (Voges et al., 2018) and the detected correlations of double standards with body dissatisfaction in this study, it might be assumed that double standards for one’s own body would be more self-deprecating in the case of participants with eating pathology, which should be examined in future studies. Furthermore, samples with a higher BMI, younger or older persons, or persons from different cultures might show different double standards in body evaluation, as body image has been found to differ across the lifespan (Quittkat et al., 2019), across BMI ranges (Calzo et al., 2012), and across cultures (Swami et al., 2010). Thus, the present results provide information about young, highly educated, and average-weight Caucasian women and men, and should be further examined in other samples.

Future studies could use experimental paradigms to clarify which mechanisms result in double standards and whether such double standards in body evaluation play a causal role in body image disturbances. A possible modification of the study design might be to measure eye movements during body evaluation in order to determine whether different identities result in differences in viewing patterns on the same body. Studies indicate that attentional biases may exist depending on identity, especially in individuals with eating disorders (Bauer et al., 2017) or body dysmorphic disorders (Waldorf et al., 2019). Furthermore, following designs for cognitive bias modification training (Dietel et al., 2020), participants could be trained to internalize double standards (e.g., “You have to work harder than others,” “Only the best is good enough for you,” “You have to be slim”), enabling it to be examined whether this manipulation results in more pronounced double standards in body evaluation and in higher body dissatisfaction. In a next step, cognitive bias modification training (Dietel et al., 2020) or evaluative conditioning paradigms (Glashouwer et al., 2018) could also be used to potentially reduce self-deprecating double standards. Furthermore, preventive strategies that emphasize the diversity and positive aspects of bodies, especially for women (Cohen et al., 2021), or seek to prevent widespread dysfunctional behaviors, such as fat talk (Mills and Fuller-Tyszkiewicz, 2017), or promote positive body talk (Alleva et al., 2021) might be promising. In particular, the newer body neutrality movement on social media which encourages women to attach less importance toward physical appearance might be a helpful approach (Cohen et al., 2021), as findings indicate that the evaluation of neutral characteristics is less biased by the identity of the person being assessed than the evaluation of very desirable or undesirable characteristics (John and Robins, 1993).

In sum, the present study extends previous findings of gender differences in applying double standards to self and other body evaluation. Women, relative to men, are self-depreciating. When their own face is attached to differently shaped bodies, they apply stricter standards of attractiveness, which may account for the prevalence of body image disturbances in women.