Lições sobre economia

What determines the degree of elasticity? First and most obvious, the number of substitutes available. The more alternatives, the easier consumers can switch. The demand for Robert de Niro may be inelastic. The only alternative seems to be Al Pacino, although some would say he is an almost perfect substitute. Hollywood first offered the part of Ricky in Casablanca to Ronald Reagan, not Humphrey Bogart. Not exactly substitutes, but [Alfred] Marshall never claimed that everyone was rational.

Todd G. Buchholz, in New ideas from dead economists

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