The optimal design of assisted reproductive technologies policies.

This paper studies the optimal fiscal treatment of assisted reproductive technologies (ART) in an economy where individuals differ in their reproductive capacity (or fecundity) and in their wage. We find that the optimal ART tax policy varies with the postulated social welfare criterion. Utilitarianism redistributes only between individuals with unequal fecundity and wages but not between parents and childless individuals. To the opposite, ex post egalitarianism (which gives absolute priority to the worst-off in realized terms) redistributes from individuals with children toward those without children, and from individuals with high fecundity toward those with low fecundity, so as to compensate for both the monetary cost of ART and the disutility from involuntary childlessness resulting from unsuccessful ART investments. Under asymmetric information and in order to solve for the incentive problem, utilitarianism recommends to either tax or subsidize ART investments of low-fecundity-low-productivity individuals at the margin, depending on the degree of complementarity between fecundity and ART in the fertility technology. On the opposite, ex post egalitarianism always recommends marginal taxation of ART.

Optimal lockdown and social welfare.

This paper examines the robustness of the optimal lockdown strategy to the postulated social welfare criterion. We show that utilitarianism can, under some conditions, imply a COVID-19 variant of Parfit's (1984) Repugnant Conclusion: for any (interior) lockdown with life periods of low quality, there must be a stricter lockdown that is regarded as better, even though this reduces the quality of life periods even more. On the contrary, the ex post egalitarian criterion (giving priority to the worst-off ex post) implies zero lockdown. Varying between its minimal and its maximal levels, the optimal lockdown is not robust to the postulated ethical criterion. We also identify a general ethical dilemma between the goal of saving lives (modeled by the Survivors Number Count axiom) and the goal of giving priority to the worst-off (Hammond Equity).

Long-term care and births timing.

Due to the aging process, the provision of long-term care (LTC) to the dependent elderly has become a major challenge of our epoch. But our societies are also characterized, since the 1970s, by a postponement of births, which, by raising the intergenerational age gap, can affect the provision of LTC by children. In order to examine the impact of those demographic trends on the optimal policy, we develop a four-period OLG model where individuals, who receive children's informal LTC at the old age, must choose, when being young, how to allocate births along their life cycle. It is shown that, in line with empirical evidence, early children provide more LTC to their elderly parents than do late children, because they face a lower opportunity cost of providing LTC. When comparing the laissez-faire with the long-run social optimum, it appears that individuals have, at the laissez-faire, too few early births, and too many late births. We then study, in first-best and second-best settings, how the social optimum can be decentralized by encouraging early births, in such a way as to reduce the social burden of LTC provision.