But individuals and firms spend an enormous amount of resources acquiring information, which affects their beliefs; and actions of others too affect their beliefs.

I recognized that information was, in many respects, like a public good, and it was this insight that made it clear to me that it was unlikely that the private market would provide efficient resource allocations whenever information was endogenous.

As I noted in my Nobel lecture, an early insight in my work on the economics of information concerned the problem of appropriability - the difficulty that those who pay for information have in getting returns.

Joseph Stiglitz Quotes