This paper analyzes self-control problems in intertemporal consumption of a sin good where current consumption imposes a negative externality on one’s future selves due to the existence of present-biased preferences. We introduce the negative externality dubbed ‘internality’； which is augmented by the cumulative distribution function of the sum of previous consumption. We show that the shot-run self with self-control problem over consumes the sin good compared to that of the long-run self without present-biased preferences. Further； we investigate the effectiveness of self-bargaining with the presence of an external control devise as possible punishment. The shortrun self faces three possible options: do nothing； accept the long-run self’s offer； or reject the offer. In the latter case an external control devices is implemented. It is shown that successful self-bargaining depends on the efficiency of the control device.

Life Cycle Assessment (LCA) of green and sustainable projects has been found to be a necessary analysis in order to include all upstream； downstream； and indirect impacts. Because of the complexity of interactions； the differential impacts with respect to a baseline； i.e.； a business-as-usual (BAU) scenario； are commonly considered to relatively compare various projects. However； as the degree of penetration of a project in the baseline increases； the popular marginal assumption does no longer hold； and the differential impacts may become inconsistent. Although various mythologies have ∗Corresponding author’s e-mail address: imriss@ieee.org (Reza Farrahi Moghaddam) ar X iv :1 40 9. 08 76 v6 [ cs .N I] 1 7 Se p 20 14