Noah Charney on "how the four main categories of art crime influence the art market."
UPDATE: Derek Fincham comments: "I think we can apply some pressure to one of his assertions, that is often mentioned in the press. I don't think there's any way to state with confidence that art theft is the third-largest grossing criminal activity, as I've argued before. Something like automobile theft surely cracks the top 3 in terms of mere monetary value. But I do think if we incorporate the intangible or cultural value of works, then perhaps art theft (including antiquities looting) may in fact be near the third-largest."