In your article on faces, there was a confounding variable in the reported experiment: smiling (14 February, p 28). Our brains seem to be hard-wired to interpret smiling positively. Nearly all of your data can be explained by it, yet the experiment does not control for smiles. Only the paired female images gave positive results, and those were the pairs that exhibited greater differences in their smiles. For example, both composite faces under the "Humorous?" heading are smiling to a similar extent, and there was no difference found between them. In the "Religious?" category, we might suppose that people would consider those who are religious to be more serious, and the image with the smaller smile is indeed chosen by the majority. The image picked in the "Lucky?" category has a bigger smile: lucky people are likely to be happy. The experiment seems only to prove that people can spot a smiley face.
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