A large number of studies has been canvassed by the growing rates of diffusion of Open Source Software. However, a formal analysis of the process of competition between open–source and proprietary software is still missing. We propose an epidemic model of innovation diffusion to deal with the...

he debate about the effectiveness of the counteracting policies against the supply of drugs, in particular of cocaine, is very lively and intense. Indeed, since many opinions are based on certain measures rather than others, the construction of reliable indicators is one of the preconditions for...

While the number of green start-ups has steadily increased around the world in response to the environmental problems demanding immediate solutions, there are several unresolved questions on the behaviour and performance of such ventures. The papers in this special issue shed light on these...