Cooperative

You may argue, like many other things in life, urgent endoscopy requests are not independent happenings - If a particular endoscopist is easy going or have a pair of gifted hands, we tend to consult him more.

In other words, one either receives no request, or a few in a go. For readers with a biochemical or medical background, it is similar to how oxygen molecules bind to hemoglobin: Most of the hemoglobin molecules either have none or four oxygen molecules, somewhere in between is uncommon. Yes, we call it cooperative binding.

Therefore, if we observe a substantially skewed endoscopy request amongst, say, five endoscopists and we conclude it does not happen by chance, the most likely explanation is a cooperative phenomenon.

In fact, based on the skewed observed distribution, an abnormally obsessive mind can actually compute the degree of cooperativeness. It is similar to what our textbook of biochemistry told us: By looking at the oxygen dissociation curve, one could actually predict a hemoglobin molecule has four oxygen binding site.

PS. What is an abnormally obsessive mind? By definition, anyone more obsessive than me is abnormal - I am the upper limit of normal.