Forensic metrology: its importance and evolution

Measurements play a fundamental role in nowadays forensic activities, especially in criminal justice. Guilt or innocence and the severity of a sentence do often depend upon the results of measurements. On the other hand, it is well-known that measurement results are always affected by uncertainty, so that any decision based on measurement results carries an implicit risk of being wrong: uncertainty helps in estimating this risk. If this concept is translated into the juridical world, it is quite immediate to recognize that uncertainty may quantify how reasonable is the doubt with which a verdict is rendered by the trier of facts. Unfortunately, forensic disciplines are still largely unaware of the basic, fundamental concepts of metrology. This paper is aimed at showing how forensic metrology is developing in different countries and reporting a few cases where metrology played a key role

A model of political enterprise.

Political organizations engaged in long-term operations are viewed as firms that sell promises: their output is the expectation of a reorganization of society. Because benefits will accrue to the organization's customers and rewards will be paid out to its workers only if and when the goal is achieved, the workers are volunteers in the sense that they engage in unpaid effort today in exchange for a probabilistic reward tomorrow. Because a market for promises is the ideal ground for reciprocal cheating, some mechanisms to ensure reciprocal trust must be devised if exchange is to take place at all. Three problems of reciprocal trust are discussed: the firm's credibility vis-a' -vis its workers, workers' shirking, and the firm's credibility vis-a' -vis its customers. It is shown that a viable solution to these problems in effect turns the political firm into a kind of producer cooperative. It is then shown that the intrinsic inefficiency of a market made up of producer cooperatives makes merger likely, until a single firm remains. Then it is argued that these trust problems are further lessened if the firm undertakes commercial production on the side, with important consequences for its behavior: this is analyzed with a formal model of a two-product cooperative. These features of the political enterprise and industry are finally shown to account for a variety of observed facts of political life.

The cult of martyrs

This paper suggests a rational explanation for extreme voluntary sacrifice in situations in which the state of the world when the decision must be made is observable only by the agent. Such explanation is the cult of martyrs, heroes, and saints. This cult may get out of control and fuel fanaticism, or excessive sacrifice from the standpoint of the sponsoring organization. A survey of the historical evidence of Christian martyrdom strongly suggests that martyrs were driven by the expectation of a cult in this world, not by otherworldly rewards. In particular, it is argued that the evidence of excess martyrdom in both Muslim Spain and the Roman Empire strongly speaks for the cult theory.martyrdom, cult, afterlife, economics of religion, principal-agent model, suicide terrorism

Radicalization as a reaction to failure: an economic model of islamic extremism

This paper views Islamist radicals as self-interested political revolutionaries and builds on a general model of political extremism developed in a previous paper (Ferrero, 2002), where extremism is modelled as a production factor whose effect on expected revenue is initially positive and then turns negative, and whose level is optimally chosen by a revolutionary or-ganization. The organization is bound by a free-access constraint and hence uses the degree of extremism as a means of indirectly controlling its level of membership with the aim of maximizing expected per capita income of its members, like a producer co-operative. The gist of the argument is that radicalization may be an optimal reaction to perceived failure (a widespread perception in the Muslim world) when political activists are, at the margin, relatively strongly averse to effort but not so averse to extremism, a configuration that is at odds with secular, Western-style revolutionary politics but seems to capture well the essence of Islamic revolutionary politics, embedded as it is in a doctrinal framework.

Optical Phase Locking techniques: an overview and a novel method based on Single Side Sub-Carrier modulation

A short overview on Optical Phase locking techniques and a detailed description of the Phase Locking technique based on Sub-Carriers modulation is presented. Furthermore, a novel Single Side Sub-Carrierbased Optical Phase Locked Loop (SS-SC-OPLL), with off the shelf optical components, is also presented and experimentally demonstrated. Our new method, based on continuous wave semiconductor lasers and optical single side sub-carrier modulation using QPSK LiNbO3 modulator, allows a practical implementation with better performance with respect to the previously proposed OPLL circuits, and permits an easy use in real time WDM signal coherent demodulation