Are Poor Cities Cheap for Everyone? Non‐Homotheticity and the Cost of Living Across U.S. Cities
研究发现，富裕城市和贫困城市提供的商品种类与价格因当地居民收入偏好而异，高收入家庭在富裕城市每美元支出的效用比低收入家庭高40%，且差异主要源于商品种类而非价格。
This paper shows that the products and prices offered in markets are correlated with local income‐specific tastes. To quantify the welfare impact of this variation, I calculate local price indexes micro‐founded by a model of non‐homothetic demand over thousands of grocery products. These indexes reveal large differences in how wealthy and poor households perceive the choice sets available in wealthy and poor cities. Relative to low‐income households, high‐income households enjoy 40 percent higher utility per dollar expenditure in wealthy cities, relative to poor cities. Similar patterns are observed across stores in different neighborhoods. Most of this variation is explained by differences in the product assortment offered, rather than the relative prices charged, by chains that operate in different markets.