FaceResearch.org has published the results of a recent experiment where experimental psychologists at the University of Glasgow in Scotland have combined the faces of women around to world to approximate the "average face" of each country. Using a modern version of the technique that Sir Francis Galton pioneered in the 1800's, multiple images of faces are aligned and composited together to form the final result.
There is already controversy surrounding the results. Some people feel that the average is "too attractive." Part of this is explained by the process. Instead of having a lot of blurry images with undefined features, this method averages the shape of the features before blending the images together. Also when blending, remember that many singular issues are "averaged away." The study also does not reveal how the participants were selected or how large the sample size actually is.
No conclusive evidence, however, on Polish women's propensity for bangs.