A new methodology for the logistic analysis of evolutionary S-shaped processes: Application to historical time series and forecasting

A new multi-logistic methodology to analyze long range time series of evolutionary S-shaped processes is presented. It conceptually innovates over the traditional logistic approach. The ansatz includes computing the residuals to an optimized multi-logistic trend curve least squares fitted to the time-series data. The elements of the residuals series are checked for autocorrelations and once detected the residuals series is further analyzed to search for eventual presence of underlying periodic structures using a truncated Fourier sine series. The method foundations ensures both a universal applicability and a capacity to disclose the existence of active clocks that can be possibly traced to the driving motors of the evolutionary character of the time series, due to the responsiveness of corresponding process to the development of economic cycles. On associating these two views, it is found that the methodology has a strong potential to improve the quality of short-term forecasts. These findings have been put to test through applications of the methodology to studying the time evolution of two commodities of strong economic and social importance (corn and steel) and good results were consistently obtained for both the analytical and forecasting aspects.     

Integrating nanotechnology into agri-food systems research in India: A conceptual framework

The implications of current trends in nanotechnology for the agri-food sector in India are assessed. Using published literature and patents data, a model to organize the information is developed through a specially designed database. The database allows mapping research themes in nanotechnology to specific sectors in the agricultural value chain to enable a rational assessment of the potential applications of nanotechnology in the agri-food sector, identifying and prioritizing research needs across the agricultural value chain, and assessing the environmental and societal implications of this emerging technology.     

Sudden stops, banking crises and investment collapses in emerging markets

We evaluate whether financial openness leaves emerging market economies vulnerable to the adverse effects of capital reversals (“sudden stops”) on domestic investment. We investigate this claim in a broad sample of emerging markets during the period 1976–2002. If the banking sector does not experience a systemic crisis, sudden stop events fail to have a significant impact on investment. Bank crises, on the other hand, have a significant negative effect on investment even in the absence of a contemporaneous sudden stop crisis. We also find that openness to capital flows worsens the adverse impact of banking crises on investment. Our results provide statistical support for the policy view that a strong banking sector which can withstand the negative fallout of capital flight is essential for countries that open their economies to international financial flows.     

A comparison of citizen and “expert” preferences using an attribute-based approach to choice

This paper explores whether expert judgements can be taken as a proxy for citizen preferences for determining investment strategies for public goods. As an illustration, we focus on the provision of Public Rights Of Way (PROW) by Local Government Authorities in England. These provide rights of passage over property to those other than the owners, and little information is available on the welfare effects of changes in the provision and use of PROW. Given limited funds, reliance on expert judgement could be a cost effective alternative for decision-making compared with stated preference surveys of citizens. Two methods are compared. The Analytic Hierarchy Process (AHP) is used to elicit expert judgement to proxy citizen preferences for different attributes of PROW. The Choice Experiment (CE) technique is then used to derive preferences directly through personal interviews with citizens. Overall it was found that judicious use of AHP by experts can, in this instance, be used to represent citizen views. However, this result may not be easily generalisable to other settings.     

Returns from social capital in open source software networks

Open Source Software projects base their operation on a collaborative structure for knowledge exchange in the form of provision or reception of information, expertise and feedback on the creation of source code. Here, we address the direction of these knowledge flows among projects throughout social networks and their impact on project success. We identify the roles of membership or contribution that individuals play within projects. We found that connections through contributors who bring their knowledge to the project, improve project success, and that connection through members, who transfer their knowledge towards other projects, enhance project success. Finally, we found that ties through shared membership and contributions hamper project success. The analysis of knowledge flows and their impact on project success imply a translation of returns from investment in social capital, where investment takes the shape of knowledge flows and the returns mean the projects’ diffusion over the network.

The asymptotic shapley value for a simple market game

We consider the game in which b buyers each seek to purchase 1 unit of an indivisible good from s sellers, each of whom has k units to sell. The good is worth 0 to each seller and 1 to each buyer. Using the central limit theorem, and implicitly convergence to tied down Brownian motion, we find a closed form solution for the limiting Shapley value as s and b increase without bound. This asymptotic value depends upon the seller size k, the limiting ratio b/ks of buyers to items for sale, and the limiting ratio of the excess supply relative to the square root of the number of market participants. This work was sponsered in part by NSF Grant DMS-03-01795.     

Not just guidelines: Pirate codes and the emergence of property rights in <Emphasis Type="Italic">The Invisible Hook</Emphasis>

Peter Leeson’s The Invisible Hook provides a readable and entertaining narrative of the hidden economics of the Golden Age of Piracy. This essay comments on one particular aspect of Leeson’s work: what we can learn from pirates about the emergence and evolution of property rights? I conclude that pirate codes had their origins in part in legally enforceable agreements and that pirates’ blend of individual and communal property rights bore some resemblance to the property rights of wandering tribal peoples.