Efficient Use of Information and Social Value of Information

This paper analyzes equilibrium and welfare for a tractable class of economies (games) that have externalities, strategic complementarity or substitutability, and heterogeneous information. First, we characterize the equilibrium use of information: complementarity heightens the sensitivity of equilibrium actions to public information, raising aggregate volatility, whereas substitutability heightens the sensitivity to private information, raising cross‐sectional dispersion. Next, we define and characterize an efficiency benchmark designed to address whether the equilibrium use of information is optimal from a social perspective; the efficient use of information reflects the social value of aligning choices across agents. Finally, we examine the comparative statics of equilibrium welfare with respect to the information structure; the social value of information is best understood by classifying economies according to the inefficiency, if any, in the equilibrium use of information. We conclude with a few applications, including production externalities, beauty contests, business cycles, and large Cournot and Bertrand games.     

Contrasting effects of urban habitat complexity on metabolic functional diversity and composition of litter and soil bacterial communities

Functional diversity and composition of soil bacterial communities affect important soil biogeochemical processes. In natural and semi-natural ecosystems, variations in habitat complexity have been shown to significantly impact both litter and soil bacterial communities. However, this remains largely untested in urban ecosystems, where human management can lead to habitat complexity combinations unobserved in rural ecosystems. We established 10 research plots in low-complexity park, high-complexity park, and high-complexity remnant habitat types (n = 30) in Melbourne, Australia. The use of organic carbon substrates by soil and litter bacteria was measured using EcoPlates to investigate the effects of habitat complexity upon metabolic functional diversity and functional composition of bacterial communities of i) soil and ii) one-year old litter. Direct and indirect effects of habitat complexity, microclimate and decomposition status upon litter microbial functional diversity and composition were also modelled using path analysis. Soil bacterial communities had significantly higher functional diversity compared to litter bacterial communities, but no significant effect of habitat complexity was apparent. The functional composition of soil bacterial communities was not affected by habitat complexity. In contrast, the functional composition of litter bacterial communities in high complexity parks and remnants was significantly different from that in low-complexity parks. The functional composition of litter bacterial communities, but not their diversity, was directly affected by habitat complexity and microclimate as well as their indirect effects upon the decomposition status of litter. Human management of urban habitat complexity can alter the functional composition of litter and soil bacterial communities without affecting their functional diversity. While this can have significant impacts on bacteria-regulated processes and ecosystem services, it also suggests that urban bacterial communities might be able to adjust to further environmental and climatic changes affecting urban ecosystems.     

Collaborative sliced inverse regression

Sliced inverse regression (SIR) is an effective method for dimensionality reduction in high-dimensional regression problems. However, the method has requirements on the distribution of the predictors that are hard to check since they depend on unobserved variables. It has been shown that, if the distribution of the predictors is elliptical, then these requirements are satisfied. In case of mixture models, the ellipticity is violated and in addition there is no assurance of a single underlying regression model among the different components. Our approach clusterizes the predictors space to force the condition to hold on each cluster and includes a merging technique to look for different underlying models in the data. A study on simulated data as well as two real applications are provided. It appears that SIR, unsurprisingly, is not capable of dealing with a mixture of Gaussians involving different underlying models whereas our approach is able to correctly investigate the mixture.     

Powers and Limits of Transnational Corporations: The Case of ADM

Abstract This analysis employs the case of lysine price fixing involving the food‐processing transnational corporation (TNC) Archer Daniels Midland (ADM) and Asian‐based firms. In an “economy and society” conceptual framework grounded in the sociology of agriculture and food, we investigate the powers and limits of TNCs in the global era. We argue that TNCs maintain significant powers which allow them to avoid the laws and regulations of nation‐states. ADM was able to organize an illegal global cartel to control the world production and price of the feed supplement lysine. In addition, TNCs' actions in the global arena are limited by their inability to trust business partners and to organize and maintain systems of social control; these roles historically have been played by the nation‐state. We conclude that despite their significant powers, TNCs' contradictory position in the global arena provides opportunities that can be used to democratize society.     

The Intermodal Bike: multi-modal integration of cycling mobility through product and process innovations in bicycle design

The paper presents the early results of the UE-FP7 project "The Intermodal Bike". The research aim is to provide a super-compactable, super-lightweight folding bicycle as a realistic solution to graft the cycling mode onto the root of the public or private transportation systems. The folding bikes now on the international market reach weighs between 12-15 kg, with a variable footprint but occupying -when compacted- an average volume of about 100 liters. To encourage the use of this vehicle and to extend it to a larger number of users with different characteristics, the research project has set its goal in increasing as possible compactness and light weight, creating a bicycle with a volume when compacted of 20 liters (reduction factor =5), with a shape of 48 × 36 × 12 cm and a weight of 5 kg. max., ensuring stability and improving vehicle usability and efficiency, during the ride and in the phase of bike folding. To achieve this goal ergonomic and usability tests have been carried out. The tests allowed to find a posture that would ensure efficiency and comfort in the ride to as many users as possible. Parallel tests were made on the vehicle usability in the urban transport system and intermodal. The need for light weight has required special studies on the optimization of the vehicle's architecture and research on super-lightweight materials.     

Relational collaboration among spatial multipoint competitors

The presence of network ties between multipoint competitors is frequently assumed but rarely examined directly. The outcomes of multipoint competition, therefore, are better understood than their underlying relational mechanisms. Using original fieldwork and data that we have collected on an interorganizational network of patient transfer relations within a regional community of hospitals, we report and interpret estimates of Exponential Random Graph Models (ERGM) that specify the probability of observing network ties between organizations as a function of the degree of their spatial multipoint contact. We find that hospitals competing more intensely for patients across multiple geographical segments of their market (spatial multipoint competitors) are significantly more likely to collaborate. This conclusion is robust to alternative explanations for the formation of network ties based on organizational size differences, resource complementarities, performance differentials, and capacity constraints. We show that interorganizational networks between spatial multipoint competitors are characterized by clear tendencies toward clustering and a global core-periphery structure arising as consequences of multiple mechanisms of triadic closure operating simultaneously. We conclude that the effects of competition on the structure of interorganizational fields depends on how markets as physical and social settings are connected by cross-cutting network ties between competitors.     

Environmental and economic assessment for the optimal configuration of a sustainable solid waste collection system: a ‘kerbside’ case study

The article presents a case study concerning the improvement of the ‘kerbside’ waste collection system, now increasingly implemented in many Italian municipalities, as an alternative to traditional bring collection, with the aim of increasing the quality of waste collection and the collection rate, in order to reduce the final impact on the environment. A planning model for an integrated waste management system based on kerbside collection is presented. A heuristic procedure is also applied in order to obtain some admissible solutions of the real problem in reasonable computational time. The economic and environmental impacts are considered as significant elements for the evaluation and validation of the obtained solutions. Five alternative configurations of kerbside system, diverging in number of sub-area, synchrony of vehicles and directionality of the arcs, are compared in an economic point of view. Finally, Life-Cycle Assessment is used as a tool to compare the overall potential environmental impacts of the alternative of kerbside collection systems and also to compare the kerbside system with the traditional bring one. The different scenarios of kerbside system are comparable in terms of damage on the impact categories, while the bring system is the worst one, in terms of damage on human health, in the consumption of resources and also for the total damage score.     

Designing the venue logistics management operations for a World Exposition

World Expositions, due to their size and peculiar features, pose a number of logistics challenges. This paper aims at developing a design framework for the venue logistics management (VLM) operations to replenish food products to the event site, through a combination of qualitative and quantitative research approaches. First, an in-depth interview methodology, combined with the outcomes of a literature review, is adopted for defining the key variables for the tactical and operational set-up of the VLM system. Second, a quantitative approach is developed to define the necessary logistics resources. The framework is then applied to the case of Milan 2015 World Exposition. It is the first time that such a design framework for a World Exposition is presented: the originality of this research lies in the proposal of a systematic approach that adds to the experiential practices constituting the current body of knowledge on event logistics.     

Inducing a desired value of correlation between two point-scale variables: a two-step procedure using copulas

AStA Advances in Statistical Analysis - Focusing on point-scale random variables, i.e. variables whose support consists of the first m positive integers, we discuss how to build a joint...     

HOUSING FINANCE AND MONETARY POLICY

We document three facts concerning how the structure of housing finance affects the monetary transmission mechanism: first, the characteristics of residential mortgage markets differ markedly across industrialized countries; second, the impact of monetary policy shocks to residential investment and house prices is significantly stronger in those countries with larger flexibility/development of mortgage markets; third, the transmission to consumption is stronger only in those countries where mortgage equity release is common and mortgage contracts are predominantly of the variable‐rate type. We then build a two‐sector DSGE model with financial constraints to rationalize those facts.