Comparison Utility in a Growth Model
比较了两种内生增长模型：一种关注个人消费与自身过去的比较（习惯形成），另一种关注与他人消费的比较。两种模型稳态增长率相同，但面对资本负冲击时，储蓄和增长的调整路径不同，且外向型模型因忽视消费外部性导致效用较低。
This paper compares the dynamics of two general equilibrium models of endogenous growth in which agents have "comparison utility." In the "inward-looking " economy, individuals care about how their consumption in the current period compares to their own consumption in the past (one way to describe this is "habit-formation " in consumption). In the "outward-looking" economy, individuals care about how their own level of consumption compares with others' consumption. While steady state growth rates are identical in the two economies, transition paths differ. For example, consider the effect of negative shock to capital. In an endogenous growth model with standard preferences, there will be no e ect on the saving rate or the growth rate of output. In both of the models that we consider, however, saving and growth will temporarily fall in response to the shock. The initial decline in saving and growth will be larger in the inward-looking case. However, since agents in the outward-looking case do not take into account the externality effect of their consumption, higher growth in this case will lead to lower utility than in the inward-looking case.