Annuity Market Imperfection, Retirement and Economic Growth

We study the effects of an annuity market imperfection on individual agents’ labour supply and retirement decisions and on the macroeconomic growth rate in an overlapping generations model with endogenous growth. We model imperfect annuities by introducing a load factor on the interest rate faced by finitely-lived agents. Our core model features age-independent wages and a constant mortality rate. In the first extension we study the implications for microeconomic decisions and macroeconomic outcomes of a hump-shaped life-cycle profile in labour productivity, whilst in the second extension we postulate a realistic mortality process. Our main findings are that the limited availability of annuities induces agents to retire early in the first two models, but later in the model with age-dependent mortality. In all cases, the general equilibrium repercussion is that economic growth is lower under imperfect annuities than with perfect annuities.annuity markets, retirement, endogenous growth, overlapping generations, demography

The paradox of phase transitions

In this thesis I present a novel solution to the paradox of phase transition, a problem that has gained extensive attention from philosophers of physics over the last twenty years. The paradox consists in the contrast between a theoretical consequence of statistical mechanics which asserts that phase transitions require infinite amounts of substance and disproving observations of phase transitions in finite systems. The fact that it is widely neglected by physicists considerably challenges the philosophical idea of the rationality of that science. Besides these philosophical worries about the apparent contradiction, the study of phase transitions illuminates a wide range of hotly debated topics from the philosophy of science, like asymptotic reasoning as a new kind of scientific explanation, the problem of indispensable counterfactual idealisations, as well as limitations of reductionism and potential emergent phenomena in physics. Unlike many other philosophers, I do not choose a revisionist approach that rectifies the theoretical approach to phase transitions in physics from a philosophical perspective, I rather argue that the paradox is the result of the underlying conception of scientific representation. In order to dissolve the paradox, I propose an alternative account of how theoretical models represent empirical objects that reflects the inherent imprecise nature of theories of empirical sciences. It successfully resolves the tension between the theoretically required infinite models and the finiteness of empirical objects, as it admits that the former represent the latter. Altogether, my thesis is evidence of the utility of the methods of general philosophy of science for the philosophy of the particular sciences. It is the first concrete application of the structuralism of theories that emphasises the importance of accounting for the imprecise nature of physical theories and shows how its central formal tool of admissible blurs successfully solves a pending problem from the philosophy of physics

Transient marginal identities and networks in early modern Madrid:The 1614 case of the ‘Armenian’, ‘Greek’ and ‘Turkish’ counterfeiters

This article centres on a trial held in Madrid in 1614 involving a group identified as ‘vagrants’ of ‘Armenian’ and ‘Greek’ background. In order to tease out the ways in which the presence of foreigners challenged the institutions and citizens, this article approaches these defendants as relationally defined actors in the urban dynamic. It reveals the tactics marginal groups employed vis-à-vis strategic attempts by the municipal government to control foreigners by assigning them identities based on ethnicity. This case-study thus calls into question notions of vagrancy and identification based on ethnicity (‘Armenian’ and ‘Greek’, in particular) in Madrid under Phillip III and IV. In doing so, it shows marginality to be a key yet elusive site for cultural encounters and collaboration in early modern Europe, in which multilingual and culturally fluid social actors related to the Armenian diaspora played a central rol

The Tragedy of Annuitization

We construct a tractable discrete-time overlapping generations model of a closed economy and use it to study government redistribution of accidental bequests and private annuities in general equilibrium. Individuals face longevity risk as there is a positive probability of passing away before the retirement period. We find non-pathological cases where it is better for longrun welfare to waste accidental bequests than to give them to the elderly. Next we study the introduction of a perfectly competitive life insurance market offering actuarially fair annuities. There exists a tragedy of annuitization: although full annuitization of assets is privately optimal it is not socially beneficial due to adverse general equilibrium repercussions.Longevity risk, Risk sharing, Overlapping generations, Intergenerational transfers, Annuity markets