What can price volatility tell us about market efficiency? Conditional heteroscedasticity in historical commodity price series

The development in the working of markets has been an important topic in economic history for decades. The volatility of market prices is often used as an indicator of market efficiency in the broadest sense. Yet, the way in which volatility is estimated often makes it difficult to compare price volatility across regions or over time for two reasons. First, if prices are non-stationary, the variance is inflated. Second, the variance of commodity prices contains information on a number of region- and time-specific factors that are not related to market efficiency. Hence, the popular coefficient of variation and related indicators are not adequate measures of the efficiency of markets and are incomparable across regions. As a solution, we suggest using a conditional heteroscedasticity model to estimate the residual (conditional) variance of commodity prices. This measure reflects how markets react to unexpected events and can therefore be seen as a measure of market efficiency. Using this approach on grain prices from the Early Modern Pisa, Paris, Vienna, and Japan, we find that the residual price volatility had declined (and market efficiency increased) in the European markets in the late sixteenth century while it remained stable in Japan.     

Fiscal harmonization in the European Union with public inputs

Fiscal harmonization among the European Union member states is a goal involving major difficulties for its implementation. Each country faces a particular trade-off between fiscal revenues generated by taxation and the productive efficiency loss induced by their respective tax code. This paper provides a quantitative analysis of these trade-offs for a number of the European Union (EU-15) member states using a dynamic general equilibrium model with public inputs. Calibration of the model for the EU-15 member states provides the following results: i) the maximum tax revenue level is relatively far from the current tax levels for most countries; ii) the cases of Sweden, Denmark and Finland are anomalous, as productive efficiency can be gained by lowering tax rates without affecting fiscal revenues; iii) in general, countries would obtain efficiency gains without changing fiscal revenues by reducing the capital tax and increasing the labor tax; and iv) capital tax harmonization to the average capital tax rate can be done with quite small changes in both fiscal revenues and output for most countries.     

Assessing the Impact of Formal and Informal Regulations on Environmental and Economic Performance of Brazilian Manufacturing Firms

This study investigates the impact of formal and informal regulations on environmental and economic performance of Brazilian manufacturing firms. We adopt a dual approach where production technology is represented by a cost function, approximated by a translog form. Pollution is considered as a negative by-product that can be modified trough using either formal regulation (inspections or sanctions) or informal regulation (community pressure). A simultaneous equation model is estimated by three-stage least squares on a sample of 404 industrial establishments located in the state of S?o Paulo, Brazil. We show that pollution abatement costs for the Brazilian manufacturing sector are different from zero which suggests that pollution emissions are affected by environmental regulation. We also demonstrate that environmental performance of firms is jointly affected by formal and informal regulation. Lastly, formal regulation is largely influenced by informal regulation and more specifically by community pressure.     

Understanding the microenterprise sector to design a tailor-made microfinance policy for Cape Verde

Two of the central challenges faced by Cape Verde at the present are the high level of unemployment and the increasing proportion of the population living in (relative) poverty. Microenterprise development can be an effective means of addressing both problems in a developing country like Cape Verde, where microenterprises account for about 50% of employment. In this paper we provide a detailed profile of Cape Verdean microenterprises and microentrepreneurs and investigate the relationship between their characteristics and the resort to outside seed capital. We find a cluster of factors—the microentrepreneur’s age, gender, level of education and reason for being self-employed—which influence significantly the probability of being in need for external start-up capital. The policy implications of these findings for the design of a specific microfinance program for Cape Verde are discussed.

Comments on : ‘The decline and rise of political economy’, by Bruce Yandle

The first part of the argument is a reformulation of Yandle's problem and a sketch of the current apologetics of Public Choice Theory and its pitfalls. In the second part it is argued that Yandle's thesis on the connection between the social value of political economy and the size of the state displays identical flaws. An improved specification is needed to save this challenging thesis.     

Determinants of knowledge-based entrepreneurship: an exploratory approach

We intend to further the research related to the factors that determine successful entrepreneurial endeavours by academic researchers, and thus put forth an exploratory model of Knowledge-Based Entrepreneurship (KBE). Given the lack of extant adequate indicators, a new scale was developed based on the most frequently cited constructs in the literature. A sample of 1,401 researchers from Portuguese universities was administered a questionnaire and the data collected permitted a validation with regards to the psychometric properties of the questionnaire, to see its applicability to the study. The findings suggest that the absence of a patenting history or start-up portfolio act as significant barriers to academic entrepreneurship. However, when the institutional strategy is to increase patenting and spin-off activities, the university should begin investing in creating a networking environment capable of reinforcing the researchers’ Social Capital. Observing the example of successful entrepreneurs motivates other researchers to consider the possibility of developing their own ventures. The Structural Equations Modelling (SEM) approach allowed for us to identify and measure the non-linear relationships that shape the core of KBE and influence the attainment of measurable outcomes aimed at encouraging entrepreneurship. A relatively high share of the variance of the dependent variables is explained by the model, ensuring their representativeness and contributing to the state-of-art of the knowledge in this research field.     

ROSA,ROSAE, ROSIS: modelling a regional open sectoral innovation system

The literature on territorial innovation modes has identified the development of a diverse set of innovation systems at multiple levels of analysis. However, there are certain gaps that do not allow their adaptation to the particularities of certain territories. Despite the multiple concepts related to innovation systems approach, the state of the art does not yet provide a useful analytical approach for a deep and comprehensive characterization of territories with a high sectoral and technological specialization. This paper introduces an analytical framework based on a regional open and sectoral innovation system, which is qualitatively tested in the Durango County (Spain). The aim of this paper is to introduce a subtype of innovation system that meets the requirements and needs of a located micro-territory with a high level of sectoral specialization.     

OCB and external–internal social networks: effects on individual performance and adaptation to change

In this study, we develop and test a model that links one's internal and external social network structures to his or her willingness and ability to adapt in a changing work context. Using a survey data from 371 employees working in 133 different branches of a large financial firm, we find that individual behaviors that explain task performance and individual adaptation to change are affected by a number of supportive social ties (size of the support network) with which one receives support inside and, mostly, outside the workplace. The results also show that individual performance and adaptation to change are affected by the level of workers' organizational citizenship behavior. We also identify a mediating effect exerted by the informational network structure (mostly an internal network) on the relationship between the support network (mostly an external network) and individual task performance.     

Extending multi-tenant architectures: a database model for a multi-target support in SaaS applications

Multi-tenant architectures (MTAs) are considered a cornerstone in the success of Software as a Service as a new application distribution formula. Multi-tenancy allows multiple customers (i.e. tenants) to be consolidated into the same operational system. This way, tenants run and share the same application instance as well as costs, which are significantly reduced. Functional needs vary from one tenant to another; either companies from different sectors run different types of applications or, although deploying the same functionality, they do differ in the extent of their complexity. In any case, MTA leaves one major concern regarding the companies’ data, their privacy and security, which requires special attention to the data layer. In this article, we propose an extended data model that enhances traditional MTAs in respect of this concern. This extension – called multi-target – allows MT applications to host, manage and serve multiple functionalities within the same multi-tenant (MT) environment. The practical deployment of this approach will allow SaaS vendors to target multiple markets or address different levels of functional complexity and yet commercialise just one single MT application. The applicability of the approach is demonstrated via a case study of a real multi-tenancy multi-target (MT²) implementation, called Globalgest.     

On the unique features of post-disaster humanitarian logistics

Logistic activity can be thought of as a socio-technical process whereby a social network of individuals orchestrates a series of technical activities using supporting systems such as transportation and communications. To understand the functioning of the entire system requires proper consideration of all its components. We identify seven key components: the objectives being pursued, the origin of the commodity flows to be transported, knowledge of demand, the decision-making structure, periodicity and volume of logistic activities, and the state of the social networks and supporting systems. Based on our analysis of the differences between commercial and humanitarian logistics, we pinpoint research gaps that need to be filled to enhance both the efficiency of humanitarian logistics and the realism of the mathematical models designed to support it.We argue that humanitarian logistics is too broad a field to fit neatly into a single definition of operational conditions. At one end of the spectrum we find humanitarian logistic efforts of the kind conducted in long-term disaster recovery and humanitarian assistance, where operational efficiency – akin to commercial logistics – is a prime consideration. At the other, post-disaster humanitarian logistic operations involved in disaster response and short-term recovery activities represent a vastly different operational environment, often in chaotic settings where urgent needs, life-or-death decisions and scarce resources are the norm. The huge contrast between these operational environments requires that they be treated separately.