Economic feasibility analysis for electrical generation from biogas in waste disposal sites in Mexico City

This article highlights the main aspects related to energy generation from biogas in a controlled landfill of Mexico City in order to determine profits and environmental benefits. The designed structures and public policies to provide waste management services in Mexico City have been exceeded. A significant increase in demand has led the government of Mexico City to base public services on rudimentary techniques using obsolete equipment. The modernization of waste disposal facilities and the diversification of services linked to waste treatment can offer several business opportunities to optimize energy generation from solid wastes. The use of landfills to dispose large amounts of waste enables the energy generation from biogas. The energy generated can diversify the electricity market and provide economic benefits to landfills managers to cover operational costs.     

Fuzzy logic and financial risk. A proposed classification of financial risk to the cooperative sector

Applying fuzzy logic to financial indicators is not a well disseminated proposal in the accounting field. This methodology allows observing the results of financial ratios with a broader perspective, showing neither completely true nor completely false results, since they can take an undetermined truthfulness value within a set of values, applying the fuzzy logic theory. The objective of this work is to introduce the reader to the application of fuzzy logic on financial risk indicators, using the ratios of one of the sector one cooperatives of Ecuador, and thus validate the level of relevance of this indicator when compared to the standardized objective of the CAMEL model and its risk rating. To apply this theory, linguistic variables were used, the ranges of which were evaluated in 0–1 scales. It was determined that the fuzzy methodology, applied to financial risks, presents a greater level of relevance toward a good credit rating, ensuring a low level of risk and a very good solvency. However, in periods of low economic activity it would stagnate in this level due to the increased risk.     

Entrepreneurship policy and targets: the case of a low absorptive capacity region

Despite the existence of a positive relationship between new firm creation and economic growth, a certain controversy still exists regarding the need for the public promotion of entrepreneurship. The recent surge of entrepreneurship policies encompasses a wide variety of instruments and goals that are mainly designed and implemented at a regional or local level, which allows for a more efficient use of public resources. Case studies are therefore a useful approach to assessing “good practices” in entrepreneurship policies. We adopt this approach to empirically analyse whether policies are targeting specific entrepreneurial projects or not in the region of Valencia. We identify the features (in relation to the entrepreneur, the sector and the characteristics of the project itself) that may influence greater access to public funding and are principally related to standard requirements for this means of financing. These variables do not address specific entrepreneurial profiles, sectors or applicant projects, thereby revealing a substantial degree of horizontal policy design. Other features, such as almost all entrepreneurial characteristics (previous experience, age, etc.), do not seem relevant in terms of receiving public funds.     

The shared reward dilemma on structured populations

In this paper we study the recently introduced “shared reward dilemma” (Cuesta et al. in J Theor Biol 251:253–263, 2008) in the presence of a structure governing the interactions among the population. The shared reward dilemma arises when the prisoner’s dilemma is supplemented with a second stage in which a fixed reward is equally distributed among all cooperators. We first extend our previous results on the equilibrium structure of this game to the case of a one-shot game taking place on a regular network. Subsequently, we consider an evolutionary version of the game on both lattices and random networks. We show that the evolutionary game on graphs exhibits important differences with the case of well-mixed populations. In particular, there exists an important parameter range in which the cooperation is boosted and a single cooperator can invade a population of defectors. We study the dependence of the cooperation levels on the neighborhood size, finding that on random networks the level of cooperation reached decreases as the neighborhood size increases. Moreover, square lattices favor cooperation more than random networks, and on them cooperation may be almost full for certain parameter regions even for large neighborhood sizes. Further, we show that the effect of the population structure is never detrimental for cooperation. We interpret our results in terms of weak versus strong temptation and discuss the nontrivial issues involved in trying to promote cooperation exogenously by means of such a reward mechanism.     

R&D decision support by parallel assessment of economic, ecological and social impact — Adipic acid from renewable resources versus adipic acid from crude oil

The concept of eco-efficiency has largely been applied along these years. This study proposes the earlier application of this concept, namely the R&D stage of a product. Together with the economic and ecological assessment, the social impacts were analysed in the production of adipic acid from renewable resources. Conventional adipic acid based on crude oil served as a benchmark. The work was carried out within the frame of the EU funded project BIOFOAM. The ecological aspects were addressed in the Life Cycle Perspective by performing a Life Cycle Assessment. The economic impacts were assessed by the application of the Life Cycle Costing under a ‘total production cost’ perspective. In this case, the addressee is interested in several steps of the value chain, but only of the steps that are related to the consortium as a single player in the value chain. The Life Cycle Working Environment method was used to assess the social impacts. Data sources were based on the project consortium, literature and statistics. Despite of the fact that the conventional routes still outperform the new bio-source based adipic acid, the application of this methodology has shown as successful way of identifying problem fields and paving further research.     

Tourists taking photographs: the long tail in tourists' perceived image of Barcelona

This study examines photographs taken by tourists of Barcelona in order to identify the perceived image of the city. Specifically, the study analyses 3100 photographs uploaded by tourist photographers on the social network Flickr. The method of analysis used was content analysis. The findings demonstrate that Barcelona's perceived image is dominated by a few very popular sights, but also contains a large number of new sights and spaces. These new elements are not of much individual value, but collectively account for a large volume and therefore have the capacity to expand the city's image. This is the long tail of Barcelona's tourist image, providing the city with a new image created by tourists themselves.     

提高农民消费质量:公共消费品供给制度创新的视角

在全面实现小康的进程中，随着我国农村居民生活消费逐步由数量满足型向质量提高型转化，农村公共消费品需求日益增加。但现实中，在城乡割裂的二元公共产品供给模式下，我国农村包括公共基础设施、义务教育、公共卫生、社会保障等在内的主要公共消费品供给明显不足。这一状况严重制约了农民消费质量的持续提高，亟待引起重视，并通过制度创新加以改进。     

The efficiency of the Spanish police service: an application of the multiactivity DEA model

In this paper the efficiency of the Spanish Police Service is analysed using Data Envelopment Analysis (DEA). The analysis concentrates on the police activities related to the solving of crimes. The theoretical and empirical study of the police production function under this dimension leads to a consideration of the units analysed as centres which carry out their activities with nonidentical technologies and using common inputs. Accordingly, the multiactivity DEA model developed by Mar Molinero (Journal of the Operational Research Society, 47, 1996, 1273-9) is applied, one that is designed to estimate the efficiency of institutions which face several production functions using shared inputs. The results demonstrate the important differences that exist between the centres with respect to the distinct activities analysed, both as regards the efficiency rates and the factors which determine them.     

Preference intensities and risk aversion in school choice: a laboratory experiment

We experimentally investigate in the laboratory prominent mechanisms that are employed in school choice programs to assign students to public schools and study how individual behavior is influenced by preference intensities and risk aversion. Our main results show that (a) the Gale–Shapley mechanism is more robust to changes in cardinal preferences than the Boston mechanism independently of whether individuals can submit a complete or only a restricted ranking of the schools and (b) subjects with a higher degree of risk aversion are more likely to play “safer” strategies under the Gale–Shapley but not under the Boston mechanism. Both results have important implications for enrollment planning and the possible protection risk averse agents seek.