Existence and stability of overconsumption equilibria

Journal article: Growth models with endogenous mortality assume generally that life expectancy is increasing with output per capita and, thus, with individual consumption, whatever its level is. However, empirical evidence supports a U-shaped relationship between consumption and mortality, implying that the monotonicity of that relation is local but not global. This paper develops a two-period OLG model where life expectancy is a non-monotone function of consumption, and where agents form myopic anticipations about life expectancy. The existence, uniqueness and stability of steady-state equilibria are studied. It is shown that overconsumption equilibria — i.e. equilibria at which consumption exceeds the level maximizing life expectancy — exist in highly productive economies with a low impatience. We identify also conditions under which there exist long-run cycles in output and longevity around overconsumption equilibria.

Author(s)

Grégory Ponthière

Journal
  • Economic Modelling
Date of publication
  • 2011
Keywords JEL
E13 E21 I12
Keywords
  • Longevity
  • Mortality
  • Growth
  • Overconsumption
  • OLG model
Pages
  • 74-90
Version
  • 1
Volume
  • 28