The Myth of the "Average Man"
We've seen that variation in physical characteristics is often well modeled by a Gaussian distribution. A characteristic of these distributions is that most people are close to the mean, with fewer and fewer people far from the mean in either direction. But as I said in the introduction of this chapter, what is true when we consider a single characteristic turns out to be counterintuitively false when we consider a few characteristics at once, and spectacularly false when we consider more than a few.
In particular, when we consider the many ways each individual differs from the average, we find that people close to average in every way are rare or nonexistent.#6260•
This observation was made most famously by Gilbert Daniels in a technical report he wrote for the US Air Force in 1952, with the title "The 'Average Man'?" In the introduction he explains that
the tendency to think in terms of the "average man" is a pitfall into which many persons blunder when attempting to apply human body size data to design problems. Actually, it is virtually impossible to find an "average man" in the Air Force population.#6262•