What kind of thing is a think tank?

They are, of course, organizations of one kind or another whether formal, informal, small, large and so on. This post from "On Think Tanks" is highlights a very obvious but critical element, namely the people who originate, lead and live in the think tank. The organization is the people, particularly at the scale which most think tanks function - small, compact, mission-driven and expertise loaded. Being small, they need to be timely, selective, and capable of acting quickly and intelligently on opportunities. That nimbleness is underpinned by having invested in capacity, intellectual and otherwise, to carry out those timely forays. Being flexible and nimble isn't about being haphazard or careless - quite the opposite.

It would be worth exploring what role conscious organizational design plays in think tank establishment and growth. If think tanks were compared against a typology of organizations, where would they end up? It would seem that the small, entrepreneurial sector of the spectrum would be well represented with a power law distribution as size increases - the bigger a think tank is, the more rare it would be.

Has anyone come across a study of this type? What would such a study tell us about the role, purpose, and future of think tanks? Are they changing more or less than other institutions in their comparative space? Do the visible aspects of a think tank reveal what is going on under that visible layer? What would we see if the top layers were peeled back?