Mortality transition and differential incentives for early retirement

Many studies specify human mortality patterns parametrically, with a parameter change affecting mortality rates at different ages simultaneously. Motivated by the stylized fact that a mortality decline affects primarily younger people in the early phase of mortality transition but mainly older people in the later phase, we study how a mortality change at an arbitrary age affects optimal retirement age. Using the Volterra derivative for a functional, we show that mortality reductions at older ages delay retirement unambiguously, but that mortality reductions at younger ages may lead to earlier retirement due to a substantial increase in the individual?s expected lifetime human wealth.     

Distribution of parallel exchange rates in African countries

This paper investigates the distribution of parallel exchange rates in African countries using exploratory data analysis techniques and model fitting. Stable laws are fitted to empirical distributions using the maximum likelihood estimation method. Empirical evidence supports the stable hypothesis these distributions are positively skewed and have tails that are much heavier than Gaussian counterparts. The stable hypothesis is further supported by the “converging variance test,” which suggests that these distributions have infinite variance.     

Capital Flight Repatriation: Investigation of its Potential Gains for Sub‐Saharan African Countries*

Abstract: Despite the substantial recent increase in capital flows to sub‐Saharan Africa (SSA), the sub‐continent remains largely marginalized in financial globalization and chronically dependent on official development aid. The current debate on resource mobilization for development financing in Africa has overlooked the problem of capital flight, which constitutes an important untapped source of funds. This paper argues that repatriation of flight capital deserves more attention on economic as well as moral grounds. On the moral side, the argument is that a large proportion of the capital flight legitimately belongs to the African people and therefore must be restituted to the legitimate claimants. The economic argument is that repatriation of flight capital will contribute to propelling the sub‐continent on a higher sustainable growth path while preserving its financial stability and independence and without mortgaging the welfare of its future generations through external borrowing. The anticipated gains from capital repatriation are large. In particular, this paper estimates that if only a quarter of the stock of capital flight was repatriated to SSA, the sub‐continent would go from trailing to leading other developing regions in terms of domestic investment. The paper proposes some strategies for inducing capital flight repatriation, but cautions that the success of this program is contingent on a strong political will on the part of African and Western governments and effective coordination and cooperation at the global level.     

Demographic structure and capital accumulation

This paper develops an overlapping-generations (OLG) model to analyze the consequences of demographic structure changes induced by an exogenous shift in the birth rate. We first show that a finite growth rate of the population that maximizes long-run capital per capita exists. Then, we examine the theoretical properties of this growth rate by showing that: (i) it corresponds to the demographic structure such that the average ages of capital holders and workers are equal; (ii) it is associated to an efficient steady state; (iii) it increases with compulsory transfers from younger to older generations. Finally, we explain why standard OLG models do not exhibit such a growth rate.     

Coups d'état and the foreign exchange market

I empirically examine the effect of coups d'état on the foreign exchange market using a monthly panel dataset covering 150 countries over the period 1980–2015. Specifically, I investigate whether foreign exchange market's participants sanction a country following a coup d'état event by allowing depreciations of its national currency against a weighted basket of currencies of its trading partners. I combine different identification strategies and find that the occurrence of a coup d'état induces a depreciation of the nominal effective exchange rate in the coup d'état country and generates negative spillover effects on neighbouring countries. Once a coup occurs, a country level of financial buffers and the flexibility of its exchange rate regime allow reducing the magnitude of the depreciation. In addition, I provide evidence that coups also increase the likelihood of experiencing a currency crisis by about 2 percentage points in coup d'état countries compared to non-coup d'état countries.     

Existence of a competitive equilibrium in the Lucas (1988) model without physical capital

This paper considers an endogenous growth model with human capital accumulation. It gives sufficient conditions and a necessary condition for the existence of a unique competitive equilibrium with externalities. These conditions are more stringent than those which prevail for the existence of an equilibrium defined as the solution to a fixed-point problem.     

Existence of solutions in continuous-time optimal growth models

This paper studies the existence of solutions in continuous time optimization problems. It provides a theorem whose conditions can be easily checked in most models of the optimal growth theory, including those with increasing returns and multi-sector economies.      

Collateral constraints and rental markets

We study a benchmark model with collateral constraints and heterogeneous discounting. Contrarily to a rich literature on borrowing limits, we allow for rental markets. By incorporating this missing market, we show that impatient agents choose to rent rather than to own the collateral in the neighborhood of the deterministic steady state. Consequently, impatient agents are not indebted and borrowing constraints play no role in local dynamics.     

Balanced cycles in an OLG model with a continuum of finitely-lived individuals

This paper studies the intertemporal equilibrium of a barter economy populated with a continuum of finitely-lived overlapping generations. Assuming isoelastic preferences and zero endowments at the beginning and the end of the individuals’ life-span, it proves the existence of an Hopf bifurcation and provides sufficient conditions on parameters for its occurrenceThe authors would like to thank an anonymous referee, Alain Venditti and Francesco Ricci for helpful comments and suggestions