Why Do Household Portfolio Shares Rise in Wealth?
发现美国家庭风险资产占比随财富增加而上升，但标准生命周期模型预测相反；通过引入基本品和奢侈品两类消费，新模型解释了这一现象，对研究家庭投资行为的学者有参考价值。
In the cross-section of U.S. households, the portfolio share in risky assets rises in wealth. The standard life-cycle model with power utility and non-tradable labor income has the counterfactual implication that the portfolio share declines in wealth. We develop a life-cycle model in which household utility depends on two types of consumption goods, basic and luxury. The model predicts that the expenditure share for basic goods declines in total consumption, and the variance of consumption growth rises in the level of consumption. When calibrated to match these two predictions in household consumption data, the model explains portfolio shares that rise in wealth.