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We propose an endogenous growth model incorporating social capital. Social capital serves only as an input in the production of human capital and it involves a cost in terms of the final good. In contrast to alternative specifications, this model ensures that social capital enhances productivity gains by playing the role of a timing belt that drives the transmission and propagation of all productivity shocks. We find that, depending on the measure of social capital, the elasticity of human capital with respect to social capital varies from 6% to 10%. Finally, we investigate the short-term dynamics and imbalance effect properties of the model, depending on the value of this elasticity. In particular, we show that when the substitutability of social capital for human capital increases, the economy is better equipped to surmount initial imbalances, as individuals may allocate more working time to the final good sector without impeding economic growth.

We consider a resource-dependent economy initially ruled by the elite. The transition from the autocratic to a more democratic regime takes place only if the citizens decide to revolt against the elite. The occurrence of a revolution primarily depends on the autocratic regime vulnerability and the level of inequalities, both being driven by the elite׳s redistribution and repression policies. First, we show that when a political transition is inevitable, the elite choose the maximum rate of redistribution to lengthen their period in office. Second, we find that the duration of the autocratic regime is linked to resource abundance, and how it relates to the elite׳s policies. More resources lead to a shorter reign of a redistributive regime, which may not be the case of a repressive regime. Finally, we interpret the Arab spring sequence in light of our findings.

When cheap fossil energy is polluting and pollutant no longer absorbed beyond a certain concentration, there is a moment when the introduction of a cleaner renewable energy, although onerous, is optimal with respect to inter-temporal utility. The cleaner technology is adopted either instantaneously or gradually at a controlled rate. The problem of optimum under viability constraints is 6-dimensional under a continuous-discrete dynamic controlled by energy consumption and investment into production of renewable energy. Viable optima are obtained either with gradual or with instantaneous adoption. A longer time horizon increases the probability of adoption of renewable energy and the time for starting this adoption. It also increases maximal utility and the probability to cross the threshold of irreversible pollution. Exploiting a renewable energy starts sooner when adoption is gradual rather than instantaneous. The shorter the period remaining after adoption until the time horizon, the higher the investment into renewable energy.