Giffen Behavior and Subsistence Consumption
首次提供吉芬行为（需求曲线向上倾斜）的真实世界证据，通过中国两省极端贫困家庭的主食价格补贴实验，发现湖南大米和甘肃小麦存在吉芬行为，且贫困程度非线性影响需求弹性，对福利政策设计有重要启示。
This paper provides the first real-world evidence of Giffen behavior, i.e., upward sloping demand. Subsidizing the prices of dietary staples for extremely poor households in two provinces of China, we find strong evidence of Giffen behavior for rice in Hunan, and weaker evidence for wheat in Gansu. The data provide new insight into the consumption behavior of the poor, who act as though maximizing utility subject to subsistence concerns. We find that their elasticity of demand depends significantly, and nonlinearly, on the severity of their poverty. Understanding this heterogeneity is important for the effective design of welfare programs for the poor.