Critical Review--Predicting Female Physical Attractiveness Waist-to-hip ratio versus thinness
... such as that proposed by Singh. He advocated the hypothesis, which is shared by many evolutionary psychologists, that, with regard to the fundamental assumption of all evolution-based theories of human mate selection, physical attractiveness is largely a reflection of reliable cues to a woman’s reproductive success and health status (Singh, 1993a, p293-294). “And waist-to-hip ratio (WHR) has been considered as a reliable morphological indicator of sex hormone profile, risk for major disease such as diabetes, hypertension, heart attack, gallbladder disease, ovarian and breast cancer and stroke, independent of overall body fat.” (Singh, 1994a, p284) As a consequence, WHR has been regarded as a wide first-pass filter, which would automatically exclude those women with low healthy status or reproductive capability (Singh, 1993a, p294). Puhl and Boland set an experiment to test whether these hypotheses are true. The study involved 240 participants, consisting of 120 male and 120 female introductory psychology students (Puhl and Boland, 2001, p32). The authors generated six photographs of two female models by using a computer. Model A had an ideal WHR (0.72) and model B had a non-ideal WHR (0.86) (Puhl and Boland, 2001, p32). Furthermore, the two models were put into three photographic images as being underweight, normal weight and underweight. Participants were then asked to rate the photograph they got across a seven-point scale on beauty (where 1 represented very unattractive, and 7 very attractive) and fecundity (where 1 represented a low fecundity, and 7 very a high fecundity) (Puhl and Boland, 2001, pp32-33). The findings of the test support the socio-cultural perspective that in industrial societies body weight is a significant predictor of female physical attractiveness (Puhl and Boland, 2001, p40). In the experiment, both male and female students judged the underweight model to be more attractive or with high fecundity, so Puhl and Boland concluded that the primary dominance of beauty was weight but not WHR. Summary of Arguments The investigation held by Puhl and Boland (2001) mainly evaluated three hypotheses concerning determinants of female physical attractiveness: 1. Female physical attractiveness is determined by WHR (Puhl and Boland, 2001, p31). If Singh’s theory is right, participants in the investigation should give the highest ratings to females who have a WHR in the ideal. 2. “Perceived body weight, particularly thinness, will account for more variance in judgments of attractiveness than WHR (Puhl and Boland, 2001, pp31-32).” 3. “Interaction will occur between both socio-cultural and evolutionary determinants of physical attractiveness (Puhl and Boland, 2001, p32).” Although their experiment was very similar to Singh’s study, the results were totally different. They found that models in underweight condition were judged to be more attractive than normal weight and over weight categories (Puhl and Boland, 2001, p40). Furthermore, they also found that fecundity ratings in the normal weight condition differed significantly from ratings in the underweight and overweight conditions (Puhl and Boland, 2001, p40). As a consequence, Puhl and Boland (2001) drew the following conclusion: 1. It is not WHR but body weight that is a significant predictor of female physical attractiveness in industrial societies (Puhl and Boland, 2001, p40). 2. Participants’ judgments of fecundity were influenced most by perceived body weight of the models (Puhl and Boland, 2001, p41). Evaluation Generally, Puhl and Boland’s (2001) experiment is precise in methodology and procedure, which seems persuasive. However, I will suspend my judgment on the credibility of their conclusion because of limitations in their study. Firstly, Puhl and Boland (2001) improved several limitations of Singh’s experiment and got some different results. They pointed out that the within-subject design used by Singh could make it easy for the participants to guess the purpose of the test and respond to the perception of what the experimenter wants, and a between-subject design can avoid this problem (Puhl and Boland, 2001). However, a between-subject design also has its own weakness. “It is simply a fact of life that subjects differ greatly. In between-subject designs, these differences among subjects are uncontrolled and are treated as error. In within-subject designs, the same subjects are tested in each condition. Therefore, differences among subjects can be measured and separated from error…. Therefore, within-subjects designs are almost always more powerful than between-subject designs.”(http://www.ruf.rice.edu, March 24th, 2004) Consequently, usage of between-subject design might lead to different outcome. For example, in this seven-point scale rating experiment, without comparison, a participant might make different ratings to the same photograph if he is given the chance to rate twice. Furthermore, a second, perhaps the biggest problem exiting in Puhl and Boland’s (2001) research is the limitation of samples in their experiment, which was already mentioned by themselves in the article. And this limitation might be more serious than they had thought. In Singh’s article (1993a), he presented his view: “This belief of vast variability within and among cultures has hampered any systematic search to determine whether there are cross-cultural commonalities in female physical attractiveness.” (Singh, 1993a, p294) Compared with the cultural-determined features, such as weight and height, Singh’s study wa...