Complex systems can be characterized by classes of equivalency of their elements defined according to system specific rules. We propose a generalized preferential attachment model to describe the class size distribution. The model postulates preferential growth of the existing classes and the steady influx of new classes. According to the model, the distribution changes from a pure exponential form for zero influx of new classes to a power law with an exponential cut-off form when the influx of new classes is (...) substantial. Predictions of the model are tested through the analysis of a unique industrial database, which covers both elementary units (products) and classes (markets, firms) in a given industry (pharmaceuticals), covering the entire size distribution. The model's predictions are in good agreement with the data. The paper sheds light on the emergence of the exponent tau approximately 2 observed as a universal feature of many biological, social and economic problems. (shrink)
Some Darwinists keep their Darwinism close to the vest. Others wear it on their sleeves. Massimo Pigliucci has it tattooed on his forehead. Indeed, his "Darwin Day" celebrations at the University of Tennessee have become an annual orgy of self-congratulation before Darwin's idol.
Massimo Renzo has recently offered a theory of legitimacy that attempts to ground the state’s right to rule on the assumption that people in the state of nature pose an unjust threat to each other and can therefore, in self-defense, be forced to enter the state, that is, to become subject to its authority. I argue that depending on how “unjust threat” is interpreted in Renzo’s self-defense argument for the authority of the state, either his premise that “those who (...) pose an unjust threat to others can be justifiably coerced in self-defense, at least when they are morally responsible for posing the threat,” or his premise that “would-be independents pose an unjust threat to those living next to them in the state of nature,” or both of them are wrong. I further argue that his premise that would-be independents pose an unjust threat by refusing to enter the state is also mistaken. Refusing to enter the state, that is, refusing to be subject to the authority of the state, is no threat at all, and hence coercing people into entering the state is no means of self-defense and incapable of enhancing security. Renzo’s deduction of state authority from the right to self-defense fails. (shrink)
If evolutionary biologist Massimo Pigliucci didn't exist, it would be necessary to invent him. His Tales of the Rational defines an intellectual space as far removed as hardcore religious fundamentalism from mainstream thinking--but it may be coming closer as scientists and skeptics launch more aggressive attacks on pseudoscience and fuzzy thinking. Pigliucci, a rising star on the evolution-creationism debate circuit, pulls out all the stops in his work, not content merely to defend science against its detractors, but eagerly undermining (...) belief in religion and the existence of any gods at all. Using writing that is strong if rarely eloquent, he defines his terms precisely, makes short work of creationists William Lane Craig and Duane Gish, challenges religious preconceptions, and even ventures to hose down the flames of pseudoscience spouting from chaos theory. Readers with any sympathy for spirituality will run face-first into statements like "I do not see what science has to gain from being reconciled with a system of superstitious beliefs that stands for the exact opposite of free inquiry.". (shrink)