BL-GARCH models and asymmetries in volatility

In this paper the class of Bilinear GARCH (BL-GARCH) models is proposed. BL-GARCH models allow to capture asymmetries in the conditional variance of financial and economic time series by means of interactions between past shocks and volatilities. The availability of likelihood based inference is an attractive feature of BL-GARCH models. Under the assumption of conditional normality, the log-likelihood function can be maximized by means of an EM type algorithm. The main reason for using the EM algorithm is that it allows to obtain parameter estimates which naturally guarantee the positive definiteness of the conditional variance with no need for additional parameter constraints. We also derive a robust LM test statistic which can be used for model identification. Finally, the effectiveness of BL-GARCH models in capturing asymmetric volatility patterns in financial time series is assessed by means of an application to a time series of daily returns on the NASDAQ Composite stock market index.     

Simulation analysis of cold chain performance based on time–temperature data

Perishable goods are a fundamental source of revenue for the retail sector; their management, however, constitutes a severe challenge for retailers and supply chain partners. A significant cost in particular is the fraction of products perished through the supply chain, which also constitutes an ethical and environmental concern. Supply chain organisation and operative characteristics have a significant influence on this matter, as in fact ensuring suitable temperature conditions for the stock-keeping units throughout the supply chain is mandatory for perishable products. Recent developments in sensing and communication technologies allow detailed monitoring and control of cold chain; however, depending on the characteristics of the supply chain, an inherent risk of perished products is often inevitable, even in the hypothesis of perfect control. This article proposes a methodology to evaluate the performance of a cold chain in terms of expected product quality at the retail store, and to estimate the expected fraction of perished products, according to the supply chain configuration. The approach is based on Monte Carlo simulation, and implements referenced shelf-life models. A real application is also presented, involving a preliminary analysis and mapping of the supply chain activities based on time–temperature data, in order to demonstrate the practicability of the approach proposed.     

Do ownership and size affect the performance of water utilities? Evidence from Estonian municipalities

Concerns regarding rising water and sewerage prices have generated a renewed interest in measuring and assessing water utility performance. An efficiency analysis can serve as a basis for price setting decisions. This article examines the influence of ownership structure and corporate size on the efficiency of Estonian water companies, and assesses the empirical efficiency gaps through the lens of corporate governance and natural monopoly theories. To assess efficiency and the influence of ownership and corporate size on efficiency, we use a Data Envelopment Analysis and truncated regression with maximum likelihood estimation as well as an ANOVA test. The study sample consists of 43 water utilities, serving more than 68% of the Estonian population. One main finding of the study reveals that ownership structure does not affect the efficiency of Estonian water utilities, while efficiency does increase with corporate size: large water utilities outperform small utilities. An additional conclusion is that the Estonian water sector is too fragmented.     

Governance and Performance of a Mixed Public-Private Enterprise: An Assessment of a Company in the Estonian Water Sector

Local governments are increasingly entering into partnerships with the private sector in the “externalization” of public service delivery. While the financial and non-financial interests of the partners involved may appear to be in opposition and potentially un-reconcilable, this is not always the case, especially where governance arrangements exist to align and balance the requirements of financial and non-financial performance. Such arrangements are analysed here with reference to Estonia’s largest water company with mixed public-private ownership. It has a business-like management that facilitates a combination of good non-financial performance (quality and affordability) and considerable financial performance (profitability).     

Local Banks Efficiency and Employment

Abstract. This work analyses the links between credit and labour markets highlighting the influence of credit market inefficiencies on employment. We argue that if banks are not efficient in monitoring the borrowers in the presence of asymmetric information, credit market imperfections have real effects. We estimate dynamic equations using system generalized method of moments (GMM) for bank loans and employment on panel data for Italian firms. The system GMM estimates indicate that the impact of credit market on employment is higher where the local financial market is less developed, asymmetric information is widespread, bank managers are less efficient in assessing the firms' solvency and do not use appropriate methods to evaluate the borrowers' payback capacity.     

Italy’s Path to Very Low Fertility: The Adequacy of Economic and Second Demographic Transition Theories

The deep drop of the fertility rate in Italy to among the lowest in the world challenges contemporary theories of childbearing and family building. Among high-income countries, Italy was presumed to have characteristics of family values and female labor force participation that would favor higher fertility than its European neighbors to the north. We test competing economic and cultural explanations, drawing on new nationally representative, longitudinal data to examine first union, first birth, and second birth. Our event history analysis finds some support for economic determinants of family formation and fertility, but the clear importance of regional differences and of secularization suggests that such an explanation is at best incomplete and that cultural and ideational factors must be considered.     

Fitting spatial regressions to large datasets using unilateral approximations

Maximum likelihood estimation of a spatial model typically requires a sizeable computational capacity, even in relatively small samples, and becomes unfeasible in very large datasets. The unilateral approximation approach to spatial model estimation (suggested in Besag 1974 Besag, J. E. 1974. Spatial interaction and the statistical analysis of lattice systems. Journal of the Royal Statistical Society. Series B (Methodological) 36 (2):192–236.[Crossref], [Web of Science ®] , [Google Scholar]) provides a viable alternative to maximum likelihood estimation that reduces substantially the computing time and the storage required. In this article, we extend the method, originally proposed for conditionally specified processes, to simultaneous and to general bilateral spatial processes over rectangular lattices. We prove the estimators’ consistency and study their finite-sample properties via Monte Carlo simulations.     

Open Cosmopolitanism and the World Social Forum: Global Resistance,Emancipation, and the Activists’ Vision of a Better World

The World Social Forum (WSF) is the world’s largest activist network to date. Its global, regional, national, and thematic events have gathered since 2001 millions of participants and thousands of civil society and social movement organisations. Its cosmopolitan vision is built on resistance to the planetary domination by neo-liberal globalisation. This paper unpacks WSF’s cosmopolitan project and reflects on its vision of emancipated individuals, convivial communities, and a just planetary society in harmony with the environment. In its open organisational space, WSF’s cosmopolitan project develops while in the process of political action rather than prior to that. At the same time, power dynamics, ideological cleavages, and pragmatic concerns about organisation and strategy challenge WSF’s ability to pursue its goals. However, it is these internal tensions that make WSF’s cosmopolitan project both more difficult to achieve and more realistic than claims of universal unity among all its participants.     

Who are the objects of positive and negative gossip at work?: A social network perspective on workplace gossip

Gossip is informal talking about colleagues. Taking a social network perspective, we argue that group boundaries and social status in the informal workplace network determine who the objects of positive and negative gossip are. Gossip networks were collected among 36 employees in a public child care organization, and analyzed using exponential random graph modeling (ERGM). As hypothesized, both positive and negative gossip focuses on colleagues from the own gossiper's work group. Negative gossip is relatively targeted, with the objects being specific individuals, particularly those low in informal status. Positive gossip, in contrast, is spread more evenly throughout the network.