O boizinho de Galton não nos engana!
É a pergunta que pode ser feita de outra forma. Podemos nos perguntar se as pessoas entendem, por exemplo, a política monetária. Como Scott Sumner falou (e eu resumi aqui, ontem), há um interessante exemplo observado por Francis Galton sobre como as pessoas, em média, formam expectativas corretamente, mesmo que ocorram desvios individuais.
Agora, veja que interessante o que chegou na minha caixa de mensagens hoje: dois economistas resolveram examinar as expectativas dos agentes para ver se eles entendem a política monetária. Citando-os:
Central bankers often emphasize the need to communicate with the public to improve their understanding of monetary policy. As the argument goes, this should allow households and firms to make better informed price- and wage-setting decisions, and improve policy effectiveness. More generally, agents’ understanding of how policies that affect their decisions are conducted is perceived to be a key ingredient in the policy transmission mechanism. This perception is guided by economic theories in which the behavior of the economy depends on the interaction between the actual conduct of policy and agents’ understanding of it.
A análise dos autores é bem simples e interessante. Vamos às conclusões (eu sei, eu sei, você já adivinhou o que eles vão encontrar, né?):
Maybe households are “empiricists” and simply repeat patterns they observe in their own experiences. In that case they might end up responding as if they understand monetary policy. The other possibility is that at least some groups of households do understand monetary policy, but may be inattentive and only think about monetary policy at times when doing so may be worth its while, or at times when monetary policy is relatively more salient. These might be times in which the labor market is weak, and unemployment makes the headlines.
Irrespective of the drivers of the business cycle variation in the pattern of responses, we can conclude that households’ beliefs about the evolution of inflation, unemployment, and interest rates – as elicited by the Michigan Survey – are related as if they had some understanding of U.S. monetary policy, particularly for the higher income (and more educated) households.
Ou seja, mais uma vez, o boizinho de Galton prevalece. Não lembra do exemplo? Reproduzo-o.
The statistician Francis Galton attended a country fair where there was a contest of guessing the weight of an ox. He looked at all the guesses, and not surprisingly found that many were very far from the actual weight. It’s not easy to guess the weight of an ox! But even though the individual members of the crowd were not very smart, the crowd was brilliant, as the median guess was within about 1% of the actual weight–even better than the “expert guesses.” In ratex we don’t even assume that much. We don’t even assume that the public is particularly good at predicting the weight of an ox, but rather that if the ox weighs 2200 pounds, the model should not assume that the public believes it weighs 1800 pounds. That the predictions are unbiased. That’s all.
Veja só que legal: dois autores brasileiros analisando a política monetária dos EUA e, claro, não é uma pesquisa qualquer: está para ser publicada no tradicional Journal of Monetary Economics. Veja: se você quer saber mais sobre política monetária, não pergunta pela cor da camisa do prof. Shikida, não lê a página de esportes do jornal e nem procura a resposta no Almanacão da Turma da Mônica. Você vai atrás do famoso JME! Sacou?
Antes que eu me esqueça…