Small Income Effects: A Marshallian Theory of Consumer Surplus and Downward Sloping Demand
形式化了马歇尔的观点：当某商品支出占收入比例很小时，收入效应也很小。在特定偏好和价格假设下，证明了需求收入导数的范数数量级为1/√n，并推导出马歇尔与希克斯福利损失近似误差随商品数增加而趋于零，且需求最终向下倾斜。
We formalize the Marshallian idea that when the proportion of income spent on any commodity is small then the income effects are small. If n is the number of goods, we show, under certain assumptions on preferences and prices, that the order of magnitude of the norm of the income derivative of demand is 1/√n. As a corollary we get that for the case of a single price change the percentage error in approximating the Hicksian Deadweight Loss by its Marshallian counterpart goes to zero at least at the rate 1/√n and that demand is downward sloping for n large enough.