The Inclusion of Stocks in Multi-species Fisheries: The Case of Danish Seiners

Efficiency analysis in fisheries has become an area of increased research. However, setting up models to perform such analyses is complicated and several important modeling issues, including choice of inputs and outputs, level of aggregation and inclusion of stock indices, have only briefly been addressed in the literature. The latter issue is addressed in this paper, using data on Danish seiners and Data Envelopment Analysis (DEA) to estimate efficiency. Production in fisheries is obviously dependent on the fish stocks, and comparing vessel efficiency, therefore, needs to account for stock developments. Three methods to include fish stocks are analyzed. It is shown that estimations based on the Catch Per Unit Effort (CPUE) stock measure differ from the estimations based on independent stock measures, and are independent of the choice of time horizon and choice of input/output measures.Data Envelopment Analysis, fish stock, multi-species fisheries, technical efficiency, Resource /Energy Economics and Policy, Q22,

Network maps of student work with physics, other sciences, and math in an integrated science course

In 2004 Denmark introduced a compulsory integrated science course the most popular upper secondary study program. One of the nation-wide course aims are for students to "achieve knowledge about some of the central scientific issues and their social, ethical, and historical perspectives". This is to be done via collaboration between the subjects, and often involves physics and another scientific subject. The official teaching plans further state that mathematics must be used for analysing data. We use network analysis to study six different implementations of the course in terms of the structure of different kinds of teaching/learning activities. By creating networks maps of each lesson, we show that teaching/learning activities in the course seldom tends to address how sciences can work together to solve a problem, but rather stages each natural science as a distinct and separate activity with a distinct identity.Comment: 4 pages, 3 figures, 1 table, based on poster presented at PERC 2017 (http://www.compadre.org/per/conferences/2017/

The classification of 2-compact groups

We prove that any connected 2-compact group is classified by its 2-adic root datum, and in particular the exotic 2-compact group DI(4), constructed by Dwyer-Wilkerson, is the only simple 2-compact group not arising as the 2-completion of a compact connected Lie group. Combined with our earlier work with Moeller and Viruel for p odd, this establishes the full classification of p-compact groups, stating that, up to isomorphism, there is a one-to-one correspondence between connected p-compact groups and root data over the p-adic integers. As a consequence we prove the maximal torus conjecture, giving a one-to-one correspondence between compact Lie groups and finite loop spaces admitting a maximal torus. Our proof is a general induction on the dimension of the group, which works for all primes. It refines the Andersen-Grodal-Moeller-Viruel methods to incorporate the theory of root data over the p-adic integers, as developed by Dwyer-Wilkerson and the authors, and we show that certain occurring obstructions vanish, by relating them to obstruction groups calculated by Jackowski-McClure-Oliver in the early 1990s.Comment: 47 page

Quota Trading and Profitability: Theoretical Models and Applications to Danish Fisheries

Using Data Envelopment Analysis (DEA), we provide a framework to analyze the potential gains from quota trading. We compare the industry profit and structure before and after a free trade reallocation of production quotas. The effects of tradable production quotas depend on several technological and behavioral characteristics, including the ability to learn best practice (catch-up) and the ability to change the input and output composition (mix). To illustrate the usefulness of our approach, we analyze a dataset from the Danish fishery. We study the industry profit and structure under each of four sets of technological and behavioral characteristics.Data Envelopment Analysis (DEA), Individual Transferable Quotas (ITQ), reallocation, technical efficiency, allocative efficiency, fishery, Agribusiness, C61, L51, Q22, Q28,

Labor Mobility in Bolivia: On-the-job Search Behavior of Private and Public Sector Employees

This paper estimates structural parameters of both a simple and an extended job separation model with the purpose of understanding constraints in the labor market in Bolivia. The results confirm the hypothesis that skilled labor is a scarce commodity in Bolivia, while unskilled labor is abundantly available. This implies that skilled employees shop around for alternative employment opportunities and quit their jobs when a better opportunity arises. The quit rate among skilled employees in the private sector is much higher than the quit rate among skilled employees in the public sector. The reverse is true for the lay-off rate, and together this suggests that the private sector has difficulties maintaining its skilled labor. The estimates of the wage sensitivity of job search effort parameters presented in this paper suggest that it would be difficult for the private sector to improve its capacity to retain skilled employees by increasing wages – skilled employees in the private sector do not seem to reduce their on-the-job search in response to higher wages. The results are consistent with the hypothesis that the public sector in Bolivia, inflated by high levels of foreign aid (about 10% of GDP), may be detracting scarce human resources from local productive sectors, potentially jeopardizing the opportunity for sustainable development.Mobility, on-the-job search, labor markets, Bolivia

The Static and Dynamic Benefits of Migration and Remittances in Nicaragua

This paper utilizes a unique three-wave panel of household data from Nicaragua, which allows a thorough exploration of the relationships between migration, remittances and household consumption. The paper distinguishes between the effects of emigration and the impacts of remittances received. There is a self-selection bias in the decision to send a migrant, as well as in the decision to receive remittances. To adequately correct for these selection biases, we develop a bivariate selection correction procedure. Perhaps surprisingly, the results show that households do not benefit (in terms of higher consumption growth) from receiving remittances, but rather from having migrants abroad. This suggests that not only money are remitted from abroad, but also something more subtle, which could be business ideas, belief systems, aspirations, patterns of social interaction, and other intangibles, which have been dubbed social remittances.Migration, Remittances, Social Remittances, Nicaragua, Bivariate Selection Correction