Implicit contract theory

In economics, implicit contracts refer to voluntary and self-enforcing long term agreements made between two parties regarding the future exchange of goods or services. Implicit contracts theory was first developed to explain why there are quantity adjustments (layoffs) instead of price adjustments (falling wages) in the labor market during recessions.

In the context of the labor market, an implicit contract is an employment agreement between an employer and an employee that specifies how much labor is supplied by the worker and how much wage is paid by the employer under different circumstances in the future. An implicit contract can be an explicitly written document or a tacit agreement (some people call the former an "explicit contract"). The contract is self-enforcing, meaning that neither of the two parties would be willing to breach the implicit contract in absence of any external enforcement since both parties would be worse off otherwise.

The interpersonal negotiation and agreement in implicit contracts contrasts with the impersonal and nonnegotiable decision making in a decentralized competitive markets. As Arthur Melvin Okun puts it: a contract market is like an "invisible handshake" rather than the invisible hand.

In traditional economic theory, a worker takes his wage as given and decides how many hours he works. The firm also takes the wage as given and decides how much labor to buy. Then wage is determined in the market to ensure total labor supply equals total labor demand. If workers supply more labor than firms demand, then the wage level should fall so that workers will work fewer hours and firms would demand more labor. Hence, when firms reduce labor demand during a recession, we should expect to see a fall in wages as well. However, in reality, firms layoff redundant workers while keeping the wage unchanged for the rest of the workforce, and the wage compensation fluctuates considerably less than employment does in a typical business cycle. Therefore, the law of supply and demand is insufficient to explain patterns in wages and employment.

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