Richard Posner, l’un des pères de l’analyse économique du droit moderne, discute du dernier ouvrage de Shiller et Akerlof (que je n’ai pas encore commencé à lire d’ailleurs…). Comme on peut s’y attendre, Posner, qui est un défenseur de la théorie du choix rationnel, est plutôt assez critique envers la thèse de A&S. Je ne suis pas forcément d’accord avec tout mais il me semble que Posner met le doigt sur certains points critiques, comme par exemple le problème qu’il peut y avoir à invoquer « l’irrationalité » des agents pour expliquer certains phénomènes là où l’hypothèse de rationalité est largement suffisante. La fin de l’article de Posner souligne ce point en prenant l’exemple de la montée du chômage en période de récession :
« As one reads this book, one has the sense that deep down Akerlof and Shiller believe that being rational is the same as being right. That is a mistake. It prevents them from entertaining the possibility that what has now plunged the world into depression is a cascade of mistakes by rational businessmen, government officials, academic economists, consumers, and homebuyers, operating in an unexpectedly fragile economic environment, and that what is retarding recovery is not the « unreasoning fear » of which Franklin Roosevelt famously spoke but the rational fears–the reasoning fear, to use Roosevelt’s idiom–of businesspeople, consumers, and officials who confront economic uncertainties for which no one had prepared them. Akerlof and Shiller invoke « fairness » and « money illusion » to explain the puzzling behavior of employment and wages in a depression. (…)
Wages do fall in a deflation, but not as far as prices; and employers do generally prefer to economize on labor costs by laying off workers rather than by reducing their wages. The resistance of workers to having their wages cut in a deflation, a resistance that in the Great Depression of the 1930s produced a sharp rise in real incomes for many workers while others were on breadlines, is ascribed by Akerlof and Shiller to workers’ sense of « fairness »–of their sense of entitlement to their existing wage–and to « money illusion, » by which they mean the failure to distinguish between the amount of money one receives as a wage (the nominal wage) and the purchasing power of the wage (the real wage). They also argue that employers deliberately « overpay » their workers in order to boost morale and loyalty. But this does not explain why nominal wages are not cut during a depression in order to maintain (not cut) real wages.
There is a simpler explanation for unemployment in depressions, one that dispenses with irrationality. A worker who, rather than being paid a flat wage, is paid a percentage of his firm’s income would be unlikely to complain when his wage dropped in a depression; he would know that his wage was variable, and he would plan his life accordingly. But if paid a fixed wage, he is likely to count on it as a steady source of income. Since depressions are rare and have unpredictable consequences, he will not have been able to protect himself from the consequences of a depression-induced cut in his wage. He is going to be upset to find that he is working as hard or harder but being paid less, and he will not be reassured by being given a lecture on deflation and purchasing power, because he will not understand or believe it. And whereas wage cuts make the entire work force unhappy, layoffs make just the laid-off workers unhappy, and since they are no longer on the premises they do not demoralize the remaining work force by their unhappy presence. The employer, for this and other reasons–such as wanting to economize on benefits and overhead and induce the remaining workers to work harder lest they be laid off too–is likely to prefer laying off workers to cutting wages. (Unemployment insurance is a factor as well.)« .