The Royal Swedish Academy of Sciences has a mischievous bent. At a time when everyone including the Queen of England wonders why economists did not anticipate the financial crisis and still cannot agree a cure, the academy awarded the Sveriges Riksbank Prize (it is not technically a Nobel) to two American professors synonymous with economic modelling. It is popular to question Thomas Sargent’s line of work these days. In the 1970s, he revelled in the complex economic models that were the foundation of the so-called dynamic stochastic general equilibrium models now ubiquitous in central bank decision making. More important, he introduced into these models the burgeoning field of rational expectations – another idea increasingly under fire.
瑞典皇家科學(xué)院(Royal Swedish Academy of Sciences)可真是喜歡“惡搞”。就在包括英國女王在內(nèi)的所有人都想知道,為何經(jīng)濟(jì)學(xué)家未能預(yù)見到金融危機(jī)、甚至到現(xiàn)在都拿不出一致對策的時(shí)候,瑞典皇家科學(xué)院卻將諾貝爾經(jīng)濟(jì)學(xué)獎(Sveriges Riksbank Prize,嚴(yán)格說來,這并非諾貝爾獎)授予了兩位堪稱“經(jīng)濟(jì)建模代名詞”的美國教授。這段時(shí)間,質(zhì)疑托馬斯?薩金特(Thomas Sargent)所從事職業(yè)的做法已經(jīng)十分流行。上世紀(jì)70年代,薩金特沉迷于復(fù)雜的經(jīng)濟(jì)模型,建立了所謂的動態(tài)隨機(jī)一般均衡模型(DSGE)。如今,央行在進(jìn)行決策時(shí)都要用到這些模型。而更重要的是,他在這些模型中引入了當(dāng)時(shí)剛開始興起的理性預(yù)期——這在眼下已經(jīng)成為又一個(gè)越發(fā)受到抨擊的觀點(diǎn)。