Comment intégrer le risque dans le calcul économique ?

In this paper, I explain why it is sensible to discount future risk free costs and benefits at a rate of 4% in the short run and of 2% in the long run. The riskiness of future cash flows must be taken into account by imputing risk premia rather than by an arbitrary increase in the discount rate. Option values must also be integrated in the analysis. This suggests that the recent reduction of the discount rate proposed by the Commissariat au Plan should not massively increase the number of public investment projects with a positive NPV if risk is correctly integrated in the cost-benefit analysis.