Working
Papers
Abstract. Pollution
reduces longevity and impedes learning through negative health effects, thus
channeling its damages on physical and human capital. In a standard overlapping
generations (OLG) model, we show that the accumulation differential between
physical and human capital imposed by pollution matters for policy analyses on
the Balanced Growth Path (BGP) and for the transitional dynamics. Two cases
derived from our model are of particular interest. One case is that two stable
BGPs emerge with a boundary demarcating the two. One BGP is desirable featuring
high economic growth and low pollution, whereas the other should be avoided
because it is associated with low economic growth and high pollution. Another
case is that economic and environmental cycles may emerge, implying inequality
between generations. These theoretical results can be related to the empirical
evidence revealed by cross-sectional and time-series data. Government
interventions can steer the economy towards the desirable BGP and eliminate the
cycles. We contribute to the literature by connecting the pollution health
effects with the capital ratio, and by identifying the capital accumulation
differential caused by pollution as a new source of economic and environmental
cycles. [Supplementary
Material]
Abstract.
We compare
pollution permits and green taxes in a unified overlapping generations
model with endogenous longevity. The model identifies pollution permits as a
potential source of multiple equilibria. One nontrivial equilibrium is an
environmental poverty trap (EPT) with low capital and a high stock of
pollution. An economy operating around the equilibrium will gravitate toward
this equilibrium in the long run. The other nontrivial equilibrium is a
desirable one with high capital and a low stock of pollution. A saddle path
leads to this desirable equilibrium. Alternatively, green taxes produce a
unique stable equilibrium that avoids the EPT. Our conclusion is that
developing countries can continue to consider pollution permits as an efficient
mechanism to improve environmental conditions but proceed with caution given
the possibility of being drawn into an EPT. [Supplementary Material]
Abstract.
In this paper, we investigate the nature of rational expectations equilibria
for economic epidemiological models, with a particular focus on the behavioral
origins and dynamics of epidemiological bifurcations. Unlike mathematical epidemiological models,
economic epidemiological models can produce regions of indeterminacy or
instability around the endemic steady states due to endogenous human responses
to epidemiological circumstance variation, medical technology change, or health
policy reform. We consider SI, SIS, SIR
and SIRS versions of economic compartmental models and show how
well-intentioned public policy may contribute to disease instability,
uncertainty, and welfare losses.
Abstract. In this paper, we
disentangle the impacts of terrorism events and the subsequent Homeland
Security Advisory System (HSAS) on visitation at U.S. National Park Service
(NPS) sites. To do this, we estimate a random effects model using a balanced
panel of monthly site visitation between 1979 and 2013, spanning the period
between two major terrorism events: 9/11
and the Oklahoma City bombing. The
estimation results show increased visitation after the 1995 Oklahoma City
bombing, but a decrease in visitation after 9/11. Visitation declines diminish the farther the
site is from the twin towers and the more time has passed since 9/11. Elevated terrorism threat levels under the
HSAS have a negative impact on visitation, but the impact of the warning dies
out over time. An interaction effect indicates that large visitation sites
close to the Twin Towers may experience more visitation after the HSAS level
increases. We suggest the negative HSAS time effect may be due to some
potential visitors choosing to stay home, while the positive interaction effect
may indicate other people substituting away from other activities toward visiting
NPS sites.