Human proportion: average vs ideal (Galton)
Following Quételet, Sir Francis Galton (1822 1911), English scientist, explorer and anthropometrist, showed that if any set of measurements within a population (e.g. the heights of all people) is normally distributed, then so are sets of similar measurements of any subgroup of that population, and vice versa. He showed too there is a correlation between the measurements of different parts of the body.
For example, for white U.S. males aged 18 to 30 years, the relationship between the height of a person and the length of the upper arm bone (humerus) is
y = 3.08x + 70.45, where y = height in cms and x = length of humerus in cms.
For white U.S. females aged 18 to 30 years, the relationship is y = 3.36x + 57.97.
The expected or standard error for males is ± 4.05 cms, for females, ± 4.45 cms.
Such relationships are important in forensic pathology and anthropology as a means of predicting the likely height and other characteristics of a body from bone measurements. More widely, such data are critical in ergonomics: the size and shape of the average person are important in designing human environments and equipment.It is interesting to ponder whether a person of the proportions of Michelangelos David would be comfortable in todays world!
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