探索當下偏誤對邊際消費傾向的影響： 結合流動性、非流動性資產與異質性個體模型

Abstract

消費習慣會根據消費者的狀態而有所不同。除了受到持有資產與所得影響，本文進一步探討不同的行為偏好 — 當下偏誤。在兩資產的框架模型下，我們發現當下偏誤大幅提升了消費者的邊際消費傾向，但同時也使得消費者的持有資產下降。藉由混合一般指數型折現偏好與具有當下偏誤折現偏好兩種型態的消費者，經過校準後的模型僅需要 4% 的流動性與非流動性資產報酬差距，就可以同時符合許多總體經濟分布數據以及實證下平均 MPC 的合理範圍。與Kaplan and Violante (2022) 的兩資產模型所需要的 8% 資產報酬差距相比，我們的模型所使用的資產報酬差更接近實證資料。

Consumer behavior can be significantly influenced by the individual's financial state, including their asset holdings and income. This thesis ventures further into this dynamic, studying the interplay between these factors and behavioral preferences, particularly the effect of present bias. Under the framework of two-asset model, we find that present bias greatly enhances the marginal propensity to consume, but simultaneously leads to a reduction in their asset holdings. By combining consumers with exponential discounting preferences and those with present-bias discounting preferences, the calibrated model requires only a 4% gap between the returns on liquid and illiquid assets. This allows it to align with a range of macroeconomic distribution data and empirical average MPC within reasonable bounds. Compared to the 8% asset return gap required by the two-asset model in Kaplan and Violante (2022), the return differential used in our model is more closely aligned with empirical data.