金融双语 非均衡与流动性过剩

Disequilibrium and Excess Liquidity

过剩与不足，或说供大于求与求大于供，都是经济中的非均衡状态。这里的供求对应于意愿的交换数量，即在市场均衡时交易者在不受数量约束的情况下，根据效用最大化原则在现行价格下进行交易的名义供求量。当意愿的交换数量与实际的交易数量不同时，就出现了非均衡。而非均衡也可以是一种均衡，又称非瓦尔拉斯均衡。非瓦尔拉斯均衡是指在一定约束条件下，构成某一经济系统的相互作用的变量经过调整后，该系统不再存在继续变动的趋势，经济处于稳定状态。如果市场是充分有效的，则实际交易需求就取决于意愿供求的短边，即遵循“短边原则”。如果市场上存在摩擦，则实际交易量就会小于意愿供求的任何一方。由于垄断等因素引起的价格刚性、配额问题以及调整成本等的存在，以及由于计划经济中的预算软约束等因素干扰了利润最大化的决策，破坏了瓦尔拉斯均衡的实现前提，使非瓦尔拉斯均衡广泛存在。对于非均衡经济，理性经济人的行为不仅取决于价格信号，还要综合考虑数量信号。

Surplus and shortage, or oversupply and excess demand, both are disequilibrium economic phenomena. Here, the supply and the demand correspond to desired amount to trade, which is the nominal amount of supply and demand that the traders deal under prevail prices without quantity limits according to the principle of utility maximization, when the market is balanced. When the desired trade amount is different from the actual amount of transactions, there comes the disequilibrium. But the disequilibrium may also be a kind of equilibrium,i.e, non-Walrasian equilibrium. Non-Walrasian equilibrium refers to a status that there is no tendency to continue changing under certain constrains after an adjustment of interactional economic variables in the system, and the system is in a stable condition. If the market is fully effective, the real demand will depend on the short side of the desired supply and demand, that is, follows the ＂short-side principle＂. If there are frictions in the market,