Yeah I like to think of it as the "Fiat Gateway" effect. When you're asking about this effect, what kind of economic impact are you referring to? Are you trying to quantify the capital inflow driven by sites like coinbase? and perhaps where this capital trickles down to, like into other alt coins.. which eventually grows the entire crypto space? I think it would definitely be something I'd enjoy reading about.
RE: The "Coinbase Effect"