The minimal dominant set is a non-empty core-extension.

A set of outcomes for a TU-game in characteristic function form is dominant if it is, with respect to an outsider-independent dominance relation, accessible (or admissible)and closed. This outsider-independent dominance relation is restrictive in the sense that a deviating coalition cannot determine the payoffs of those coalitions that are not involved in the deviation. The minimal (for inclusion) dominant set is non-empty and for a game with a non-empty coalition structure core, the minimal dominant set returns this core.

The coalition structure core is accessible.

We prove the existence of an upper bound for the number of blockings required to get from one imputation to another provided that accessibility holds. The bound depends only on the number of players in the TU game considered. For the class of games with non-empty cores this means that the core can be reached via a bounded sequence of blockings. Primitive recursive algorithms are provided to locate accessibility paths.Structure;

From research to farm : ex ante evaluation of strategic deworming in pig finishing

This paper upgrades generic and partial information from parasitological research for farm-specific decision support, using two methods from managerial sciences: partial budgeting and frontier analysis. The analysis focuses on strategic deworming in pig finishing and assesses both effects on economic performance and nutrient efficiency. The application of partial budgeting and frontier analysis is based on a production-theoretical system analysis which is necessary to integrate parasitological research results to assess aggregate economic and environmental impacts. Results show that both statistically significant and insignificant parasitological research results have to be taken into account. Partial budgeting and frontier analysis appear to be complementary methods: partial budgeting yields more discriminatory and communicative results, while frontier methods provide additional diagnostics through exploring optimization possibilities and economic-environmental trade-offs. Strategic deworming results in a win-win effect on economic and environmental performances. Gross margin increases with 3 to 12 € per average present finisher per year, depending on the cyclic pig price conditions. The impact on the nutrient balance ranges from +0.2 to –0.5 kg nitrogen per average present finisher per year. The observed efficiency improvements are mainly technical and further economic and environmental optimizations can be achieved through input re-allocation. A user-friendly spreadsheet is provided to translate the generic experimental information to farm-specific conditions

A microscopic model for Josephson currents

A microscopic model of a Josephson junction between two superconducting plates is proposed and analysed. For this model, the nonequilibrium steady state of the total system is explicitly constructed and its properties are analysed. In particular, the Josephson current is rigorously computed as a function of the phase difference of the two plates and the typical properties of the Josephson current are recovered

Flexible quota constraints in positive mathematical programming models

To explain over- and underuse of available quota, Buysse et al. (2007) have integrated the shadow cost of the quota constraint in a quota flexibility function in a positive mathematical programming model. This method and central hypothesis, formulated and tested for the case of Belgian sugar beet farms, is in current paper extended and confirmed for the cases of Flemish dairy quota and manure emission rights. Despite the different organisation, objectives and implementations of the diverse quota systems, the results are similar. A higher utilisation of quota is significantly driven by the quota rent, but farm characteristics are also important and the effect declines with increasing quota rent. Regardless the quota, the dairy quota flexibility behaviour of the sample of Flemish farms results in an output price elasticity of 0.6%. The quota flexibility functions can be used for policy analysis, model sophistication and farm advisory instrument.Quota, flexibility, Positive Mathematical Programming, farm model, Common Agricultural Policy, Agricultural and Food Policy, Demand and Price Analysis, Research Methods/ Statistical Methods,

Fertilization: trade-offs between manure abatement and plant productivity

In 2005, 30% of the Flemish farms faced a manure excess, while at aggregated level still 9.7% of the emission rights were unused. This means that, despite the various possibilities, Flemish farmers do not succeed in an effective exchange of manure between farms. In current paper is shown how inorganic fertilizer use influences the use and exchange of organic nitrogen. Because of the mutual interdependency between organic and inorganic nitrogen emission rights (or quota), inorganic nitrogen use limits the emission rights for organic nitrogen. Utilisation of these emission rights are analysed as a trade-offs choice between plant productivity (use of inorganic nitrogen) and manure disposal, as the major abatement alternative of manure production. Farmers still prefer inorganic fertilizers because of their effect on plant productivity and income. However, by changing the quota rent of organic nitrogen, the fertilization behaviour can be influenced. A higher quota rent of organic nitrogen would increase the use of manure. This trade-off behaviour seriously influences effectiveness of policies. When the objective is to lower the total nitrogen use, a mere reduction of organic quota can partially be counteracted by a higher inorganic nitrogen use. When the objective is to better spread the manure, increasing the quota rent for deficit farms will increase their acceptance of manure.manure abatement, nutrient emission rights, Tobit model, Crop Production/Industries,

A FARM LEVEL ANALYSIS OF THE RELATION BETWEEN CAP REFORMS AND LOCAL ENVIRONMENTAL LEGISLATIONS: HOW AND IN WHICH EXTENT FLEMISH DAIRY FARMERS CAN FILL UP EXTRA MILK QUOTA?

The agricultural policies shift gradually from EU-level organised market interventions to local organised environmental policies. This paper explores the growth possibilities of the Flemish dairy sector with the outlook of a quota abolishment as a case study of this policy shift. The dairy quota policy seems very restrictive for the highly profitable Flemish dairy sector, but the environmental restrictions from the manure regulation can limit the growth of the dairy sector as well. The paper uses a spatial multi-agent simulation model applied to a sample of 40.000 farms to estimate price development of emission rights and their possible impact on the growth of the dairy production. The results show that a higher milk production leads to higher prices for emission rights. However, the increased cost of manure emission rights is not expected to impede dairy farm growth because the current milk quota rent estimates go far beyond the cost of manure emission rights.milk quota, manure emission rights, mathematical programming, Flanders, Agricultural and Food Policy, Industrial Organization, Research Methods/ Statistical Methods, C02, C61, L11, Q18,