Modelling the Effect of Policy Reform on Structural Change in Irish Farming

End of project reportThe Mid Term Review (MTR) of the Common Agricultural Policy (CAP) has allowed for the decoupling of all direct payments from production from 2005 onwards; until then, most direct payments were coupled to production, requiring farmers to produce specific products in order to claim support. After decoupling, farmers will receive a payment regardless of production as long as their farm land is maintained in accordance with good agricultural practices. Direct payments to farmers have been an integral part of the CAP since the 1992 Mac Sharry reforms. Throughout the 1990s, market prices for farm produce have declined generally in line with policy while costs of production have continued to increase. Meanwhile, direct payments increased in value, increasing farmers’ reliance on this source of income. Furthermore, farmers adapted farming practices to maximise their receipt of direct payments, leading to the culture of ‘farming the subsidy’. By 1997, on cattle and tillage farms in Ireland 100 per cent of family farm income was derived from direct payments, meaning that on average the market-based revenue was insufficient to cover total costs

Modelling Probabilistic Wireless Networks

We propose a process calculus to model high level wireless systems, where the topology of a network is described by a digraph. The calculus enjoys features which are proper of wireless networks, namely broadcast communication and probabilistic behaviour. We first focus on the problem of composing wireless networks, then we present a compositional theory based on a probabilistic generalisation of the well known may-testing and must-testing pre- orders. Also, we define an extensional semantics for our calculus, which will be used to define both simulation and deadlock simulation preorders for wireless networks. We prove that our simulation preorder is sound with respect to the may-testing preorder; similarly, the deadlock simulation pre- order is sound with respect to the must-testing preorder, for a large class of networks. We also provide a counterexample showing that completeness of the simulation preorder, with respect to the may testing one, does not hold. We conclude the paper with an application of our theory to probabilistic routing protocols

GENEDEC

End of Project reportGENEDEC was a European project funded under the 6th Framework. It was co-ordinated by INRA Grignon with ten European partners and a time frame of 42 months. The purpose of the project was to conduct a quantitative and qualitative assessment of the socio-economic and environmental impacts of the decoupling of direct payments on agricultural production, markets and land use in the EU. It was envisaged that the pan-EU nature of the project would facilitate an international comparison of the effects of decoupling and would provide policy makers with sufficient information to identify the key winners and losers from decoupling throughout the EU. The project aimed to provide insights into the workability of decoupling and its impacts, and to analyse alternative policy options to improve the agricultural support system. Specifically, through the use of farm level models, this project estimated the effects of existing and proposed decoupled support schemes on production, land use and land prices and the implications for farm incomes and the future structural development of farms. The project was divided into 9 Work Packages depending on objectives and time frame of the project. The main role of RERC Teagasc was in Work Package 2 which aimed to develop farm level mathematical models and used the models developed to determine the impact of decoupling on Irish farms. The work in RERC started in November 2004 and ended in May 2006. A brief description of the models developed and results generated by RERC is provided here.GENEDEC was a European project funded under the 6th Framework

Using higher-order contracts to model session types

Session types are used to describe and structure interactions between independent processes in distributed systems. Higher-order types are needed in order to properly structure delegation of responsibility between processes. In this paper we show that higher-order web-service contracts can be used to provide a fully-abstract model of recursive higher-order session types. The model is set-theoretic, in the sense that the meaning of a contract is given in terms of the set of contracts with which it complies. The proof of full-abstraction depends on a novel notion of the complement of a contract. This in turn gives rise to an alternative to the type duality commonly used in systems for type-checking session types. We believe that the notion of complement captures more faithfully the behavioural intuition underlying type duality.Comment: Added definitions of m-closed terms, of 'dual', and a discussion to show the problems of the complement functio

Modeling Stochastic Crop Yield Expectations with a Limiting Beta Distribution

The use of plausible stochastic price processes in price risk analysis has allowed advances not seen in crop yield risk analysis. This study develops a stochastic process for yield modeling and risk management. The Pólya urn process is an internally consistent dynamic representation of yield expectations over a growing season that accommodates agronomic events such as growing degree days. The limiting distribution is the commonly used beta distribution. Binomial tree analysis of the process allows us to explore hedging decisions and crop valuation. The method is empirically flexible to accommodate alternative assumptions on the growing environment, such as intra-season input decisions.crop abandonment, crop insurance, derivative analysis, growing degree days, Pólya’s urn, stochastic process, Crop Production/Industries,

Feeding and the Equilibrium Feeder Animal Price-Weight Schedule

Feeder animal prices depend on fed animal prices, the biological growth technology, and feed costs. In addition, daily maintenance costs can be avoided through accelerated feeding. These observations allow us to model optimal feeding under equilibrium feeder animal pricing. Our model enables a better understanding of regulation in feedstuff markets. The feeder animal price-weight schedule is likely decreasing and convex in weight. Prices for animals with better growth potential should be less sensitive to feed and fed animal prices. Prices for lighter animals should be more sensitive to these prices. Regression analyses on Southern Great Plains cattle prices provide support for this model.days on feed, energy use, feed ban, growth hormones, Kleiber's law, ration density, veal market, Livestock Production/Industries,

Seasonality and Costs of Production on Irish dairy farms from 1994-2008

working paperPrevious research has highlighted the economic advantages of spring calving in countries such as Ireland that have a long spring/summer grazing season. However, the widespread adoption of such a production system leads to a highly seasonal milk supply and a range of problems that are associated with seasonality. The objective of this paper is to use historical data to quantify the economic benefits of a spring calving system. Data from over 400 dairy farms in Ireland over a period of 15 years is examined. Fixed, random and between effects panel models are estimated to test the significance of calving season on production costs. The results show the effect of calving season is significant at lowering production costs. These models returned results suggesting that high compact early Spring herds have significantly lower costs than over seasons. However the fixed effect model demonstrates little difference between production costs in different seasons suggesting individual effects such as the ability of the farmer may play a role in reduction of costs. Herds that are calved over a shorter period tend to have lower production costs

Acquisition Values and Optimal Financial (In)Flexibility

In this paper, the authors analyze optimal financial structure for an incumbent and potential entrant accounting for feedback effects in secondary asset markets.Financial Flexibility; Market Entry; Acquisition; Exit Values; Predation; Financial Contracting; Product Market Competition

Compositional Reasoning for Explicit Resource Management in Channel-Based Concurrency

We define a pi-calculus variant with a costed semantics where channels are treated as resources that must explicitly be allocated before they are used and can be deallocated when no longer required. We use a substructural type system tracking permission transfer to construct coinductive proof techniques for comparing behaviour and resource usage efficiency of concurrent processes. We establish full abstraction results between our coinductive definitions and a contextual behavioural preorder describing a notion of process efficiency w.r.t. its management of resources. We also justify these definitions and respective proof techniques through numerous examples and a case study comparing two concurrent implementations of an extensible buffer.Comment: 51 pages, 7 figure

Study on the Functioning of Land Markets in the EU Member states under the Influence of Measures applied under the Common Agricultural Policy

End of project reportStudy on the Functioning of Land Markets in the EU Member states under the Influence of Measures applied under the Common Agricultural Polic