Diversified Portfolios in Continuous Time

We study a financial market containing an infinite number of assets, where each asset price is driven by an idiosyncratic random source as well as by a systematic noise term. Introducing 2 asymptotic assets" which correspond to certain infinitely well diversified portfolios we study absence of (asymptotic) arbiytrage, and in this context we obtain continuous time extensions of atemporal APT results. We also study completeness and derivative pricing, showing that the possibility of forming infinitely well diversified portfolios has the property of completing the market. It also turns out that models where the all risk is of diffusion type are qualitatively quite different from models where one risk is of diffusion type and the other is of Poisson type. We also present a simple martingale based theory for absence of asymptotic arbitrage.Large economies; diversifiable risk; APT; asymptotic arbitrage; completeness; martingales

Computers in Context — But in Which Context?

This is a case study of industrial systems development. In the project studied, an advanced computer application was developed with the intention of supporting complex, cooperative work. The project participants all viewed the emerging computer application in context. However, different contexts were used by each group of actors. Since the application was placed in contexts well known by the participants, and within which their own expertise could be applied, this phenomenon could be seen as an advantage. However, a drawback was that the participants could easily misinterpret each other. They also restricted their actions to qualities which were important for the relation between the application and the particular context visible for each actor. In conclusion, systems development must transcend these limitations, while at the same time take advantage of the focusing effect each of the contexts provide

Excessive Trademark Protection Where is the line? A study on the conflict between European Trademark and Competition Law

In today's market trademarks are extremely valuable. The proprietors need to be creative in order to prevent infringements of their trademarks. However, the CJEU have ruled that proprietors are not allowed to take measures that limit the competition of the Union without any positive effects for the benefit of consumers. The Commission has proposed amendments to the trademark legislations of the Union which will generate more legal certainty and also some stronger protection for trademark proprietors. Still, the decisions made by the CJEU will not be changed and the negative attitude, from the past, against trademarks seems to still be present, limiting trademark proprietors to an extent that they cannot protect their trademarks’ image thus risk diminishing the trademarks’ existence

Reared to become wild-like: addressing behavioral and cognitive deficits in cultured aquatic animals destined for stocking into natural environments-a critical review

Hatchery-reared aquatic animals tend to perform worse in natural environments than wild conspecifics. This was pointed out over a century ago and while there are many possible causes, one persistent observation is that unnatural rearing environments cause behavioral expressions unsuitable for a life in the wild. Behavioral traits being adaptive in barren, food-rich, and predator-free hatchery tanks likely differ from those being adaptive in nature. More recently, suspicions of cognitive deficiencies due to sensory deprivation have also been raised. Over the last few decades, substantial research has been devoted to produce more wild-like phenotypes in animals reared for stocking. This research includes life skills training programs, where animals learn to cope with important features of the natural environment (e.g., live food and predation risk), and environmental modifications aimed at stimulating the formation of adequate cognitive and behavioral traits (e.g., environmental enrichment and reduction of the number of individuals per tank). The main purpose of this paper is to provide a summary of the current state-of-knowledge of interventions aimed at ameliorating cognitive and behavioral deficiencies in aquatic animals reared for stocking. Furthermore, it aims to provide a foundation to assist in the development of future questions, hypotheses, and experiments to eventually improve the postrelease performance of these animals

Interspecific association of brown trout (Salmo trutta) with non-native brook trout (Salvelinus fontinalis) at the fry stage

The introduction of non-native brook trout (Salvelinus fontinalis) in Europe has led to displacement and decreasing populations of native brown trout (Salmo trutta). Some studies have found that brown trout shift to a diet niche similar to brook trout when the two species live in sympatry, which conflicts with the competitive exclusion principle. A change in feeding niche may be a sign of early interspecific association and social learning, leading to behavioral changes. As a first step to address this possibility, it is essential to assess the interspecific association between the species during the early ontogenetic life stages. In this study, we therefore assess whether juvenile brown trout associate with non-native juvenile brook trout to the same extent as with conspecifics by setting up two experiments: (i) a binomial choice test allowing visual and chemical cues to estimate the species specificity of group preference, and (ii) an association test without physical barriers to estimate the degree of association of a focal brown trout with a group of either conspecifics or heterospecifics. In experiment (1), we found that focal juvenile brown trout preferred to associate with the stimuli groups and did not discriminate either against conspecific or heterospecific groups. Furthermore, more active individuals showed stronger preference for the stimuli group than less active ones, regardless of species. In experiment (2), we found that brook trout groups had a tighter group structure than brown trout groups, and that focal brown trout showed stronger association with brook trout than with brown trout. These results indicate that brown trout may associate with brook trout at an early life stage, which would allow for interspecific social learning to occur. Future studies should look closer into causes and consequences of interspecific association and social learning, including potential effects on the phenotype selection in brown trout populations

Behavioural repeatability in larval Limnephilus lunatus Curtis, 1834 (Trichoptera) in an open-field test

This article investigates inter-individual repeatability in distance moved in an open-field test for larval Limnephilus lunatus Curtis, 1834. Repeatability across four trials (two-day trial intervals) was comparable to previous studies on arthropod species (repeatability: R = 0.37), indicating that L. lunatus is a suitable model species in this research field. Two potential nuisance factors were corrected for: (1) progressively declining activity over consecutive trials and (2) case mass:body mass ratio, affecting activity negatively. These factors require consideration in behavioural experiments on larval caddisflies. Pairwise correlations of distance moved among trial days showed that behaviour in the first trial did not correspond well with behaviour in the following trials. Re-analysing the data using only trials 2 to 4 increased the repeatability (repeatability: R = 0.50), suggesting that future studies should consider not including data derived from initial trials, as the initial trial may constitute a different context than the following ones

The Employment Contract as the Materialization of the Social Order. Contracts at Albert Ranft’s Stockholm theatres, 1895-1926

In the archive, the materialized traces of theatrical organization and performances remain. In this paper, we focus on the employment contract, as a type of source material commonly found but rarely studied in theatre studies. Empirically, the paper is based on a study of contracts from Albert Ranft’s Stockholm theatres, 1895-1926. Ranft built his commercially funded theatrical empire in Stockholm in a period when the competition from subsidized theatre was minimal, and for a time dominated the Stockholm theatres. The study demonstrates how the study of employment contracts allows us to form an understanding of power relations between managers on the one hand, and artists and directors on the other, and also the formal and social aspects of the employment contracts. In the case of Albert Ranft, the contracts bear evidence of his dominant position in Stockholm theatre, which in turn afforded him an unusually powerful position in relation to his employees. The relationship between the formal and social contract is explored, and it is suggested that the formal contract could be seen as a photographic negative of the social contract: if there is an extensive social contract, the formal contract will be more elaborate, and vice versa. The extensive formal contracts of the studied period might therefore be seen as evidence of a relatively thin social contract, implying that industry norms were, at the time, not institutionalized enough to be taken for granted

The State of Numeracy Education in Latin America and the Caribbean

Through this review we have sought to further understanding of the state of preprimary, primary, and secondary numeracy education in Latin America and the Caribbean (LAC). Research on the opportunities available to students in the region presents a troubling picture. Young people are not being properly prepared for the numeracy requirements of an increasingly interconnected world economy. Culprits include weak curricula, inadequate learning materials, and teachers¿ lack of proficiency in mathematics and the natural sciences

Challenges of Measuring Performance of the Sales and Operations Planning Process

The purpose of this study is to identify and structure challenges of measuring performance of the Sales and Operations Planning (S&OP) process. A multiple case study methodology was applied. Qualitative data was collected via 22 structured interviews with managers from six case companies in various industries. A process oriented framework was proposed by structuring the challenges based on two key areas of process performance (effectiveness and efficiency) and different maturity levels of the process. A major challenge for all the cases, regardless of their maturity level, relates to defining of cross-functional trade-offs measures. Another major challenge was alignment of measures with business strategy and reward system. Additional common challenges for the different maturity levels were also found. While confirming some challenges from previous research, this study also finds new challenges, especially for more mature levels. Examples are standardization to support unbiased decision making, but also customization of measures for various organizational levels, and visualization of findings from the measurement to facilitate analysis. However, future research must validate and extend the results in other industries. The results offer challenges from a process oriented view and can serve as insights for managers when designing and implementing the S&OP process measures, or advancing from one maturity level to another. This research enhances understanding of the challenges to measure the S&OP process performance and adds to the S&OP literature and performance measurement literature