Credit market segmentation, essentiality of commodities, and supermodularity
研究了在信贷市场分割和价格依赖交易约束下，不完全市场经济中均衡的存在性，发现当商品具有必要性或效用函数为凹且超模时均衡存在，适用于包含模糊性和无追索权抵押贷款的经济。
We consider incomplete market economies where agents are subject to price-dependent trading constraints compatible with credit market segmentation. Equilibrium existence is guaranteed when either commodities are essential, i.e, indifference curves through individuals’ endowments do not intersect the boundary of the consumption set, or utility functions are concave and supermodular. The smoothness of mappings representing preferences, financial promises, or trading constraints is not required. Hence, we may include in our framework economies where ambiguity is allowed and agents maximize the minimum expected utility over a set of priors, or where markets include non-recourse collateralized loans.