'Perceived as random' seems like a pretty junk measure of other humans' efforts at producing randomness. Garbage in, garbage out. Surely analysing this tells you absolutely nothing about anything?
I would understand if the actual measurement is not perceptual but mechanised, i.e. "how small can we compress this stream of random choices using our best known compression methods" or something. (But then a stream of 10 symbols is surely not enough to show you the humans.)
It gets pretty theoretical, but basically it's estimating the Kolmogorov complexity by looking at the size of the Turing machine required to generate a particular string, rather than Shannon entropy or implementations of common compression techniques.
I would understand if the actual measurement is not perceptual but mechanised, i.e. "how small can we compress this stream of random choices using our best known compression methods" or something. (But then a stream of 10 symbols is surely not enough to show you the humans.)