Modelling dairy farm size distribution in Poland using an instrumental variable generalized cross entropy markov chain approach

The aim of this paper is to analyse the evolution of the dairy farm structure of Poland during the post-socialist period. First the paper focuses on how the farm structure has changed over time and what path it is likely to follow in the coming decade. Second, it is tested whether the evolution of farm size is explained by non-stationary effects. Finally, several statistical indicators are computed on farm mobility and on which farms are likely to survive. An instrumental variable generalised cross entropy Markov chain approach which incorporates prior information is applied for estimation. Prior information included general and plausible information on farm mobility and structural adjustments based on independent literature. The projections show that dairy farm numbers will continue to decline, although accompanied by an increase in the number of medium-sized and large farms. Subsistence dairy farms are expected to slowly leave the sector in the coming decade

The 'milk quota rent puzzle' in the EU: economic significance, review and policy relevance

In the so-called Common Agricultural Policy (CAP) 'Health Check' the European Commission has recently proposed gradual transitional measures to allow a 'soft landing' of the milk sector to quota expiry. The aim of this paper is to support policy makers to get better insights in the implications of some of the most important economic assumptions and empirical choices made in partial equilibrium models focusing on dairy. Three partial equilibrium models are considered: the Agricultural Member states MODeling (AGMEMOD) model, the Common Agricultural Policy SIMulation (CAPSIM) model, and the European Dairy Industry Model (EDIM). The paper analyzes how the most important economic supply components, as they are part of the three key dairy models, affect milk production projections. A main conclusion is that the evaluation of the contribution of a study should not be based on one single characteristic (such as quota rents, supply responses). One isolated characteristic is not able to explain finally obtained model outcomes. Quota rents, supply responses, shifters and the demand side have to be integrated with each other

THE 'MILK QUOTAS RENT PUZZLE' IN THE EU: ECONOMIC SIGNIFICANCE, REVIEW, AND POLICY RELEVANCE

In the so-called Common Agricultural Policy (CAP) 'Health Check' the European Commission has recently proposed gradual transitional measures to allow a 'soft landing' of the milk sector to quota expiry. The aim of this paper is to support policy makers to get better insights in the implications of some of the most important economic assumptions and empirical choices made in partial equilibrium models focusing on dairy. Three partial equilibrium models are considered: the Agricultural Member states MODeling (AGMEMOD) model, the Common Agricultural Policy SIMulation (CAPSIM) model, and the European Dairy Industry Model (EDIM). The paper analyzes how the most important economic supply components, as they are part of the three key dairy models, affect milk production projections. A main conclusion is that the evaluation of the contribution of a study should not be based on one single characteristic (such as quota rents, supply responses). One isolated characteristic is not able to explain finally obtained model outcomes. Quota rents, supply responses, shifters and the demand side have to be integrated with each other.milk quota rents, supply response, shifters, dairy policy, equilibrium models., Agricultural and Food Policy, Political Economy, Research Methods/ Statistical Methods, C01, C02, Q12, Q13.,

Modelling the Dairy Farm Size Distribution in Poland Using an Instrumental Variable Generalized Cross Entropy Markov Approach

The aim of this paper is to analyse the evolution of the dairy farm structure of Poland during the post-socialist period. First the paper focuses on how the farm structure has changed over time and what path it is likely to follow in the coming decade. Second, it is tested whether the evolution of farm size is explained by non-stationary effects. Finally, several statistical indicators are computed on farm mobility and on which farms are likely to survive. An instrumental variable generalised cross entropy Markov chain approach which incorporates prior information is applied for estimation. Prior information included general and plausible information on farm mobility and structural adjustments based on independent literature. The projections show that dairy farm numbers will continue to decline, although accompanied by an increase in the number of medium-sized and large farms. Subsistence dairy farms are expected to slowly leave the sector in the coming decade.dairy, farm size, Poland, Markov chain, generalised cross entropy., Livestock Production/Industries,

Sharpening mT2m_{T2} cusps: the mass determination of semi-invisibly decaying particles from a resonance

We revisit mass determination techniques for the minimum symmetric event topology, namely $X$ pair production followed by $X \to \ell N$, where $X$ and $N$ are unknown particles with the masses to be measured, and $N$ is an invisible particle, concentrating on the case where $X$ is pair produced from a resonance. We consider separate scenarios, with different initial constraints on the invisible particle momenta, and present a systematic method to identify the kinematically allowed mass regions in the $(m_N, m_X)$ plane. These allowed regions exhibit a cusp structure at the true mass point, which is equivalent to the one observed in the $m_{T2}$ endpoints in certain cases. By considering the boundary of the allowed mass region we systematically define kinematical variables which can be used in measuring the unknown masses, and find a new expression for the $m_{T2}$ variable as well as its inverse. We explicitly apply our method to the case that $X$ is pair produced from a resonance, and as a case study, we consider the process $pp \to A \to \tilde \chi_1^+ \tilde \chi_1^-$, followed by $\tilde \chi_1^\pm \to \ell^{\pm} \, \tilde \nu_{\ell}$, in the Minimal Supersymmetric Standard Model and show that our method provides a precise measurement of the chargino and sneutrino masses, $m_X$ and $m_N$, at $14 \, \mathrm{TeV}$ LHC with $300 \, \mathrm{fb}^{-1}$ luminosity.Comment: 18 pages, 13 figures, version 2 updated to JHEP 06 (2014) 17

The Universal Rotation Curve of Spiral Galaxies. II The Dark Matter Distribution out to the Virial Radius

In the current LambdaCDM cosmological scenario, N-body simulations provide us with a Universal mass profile, and consequently a Universal equilibrium circular velocity of the virialized objects, as galaxies. In this paper we obtain, by combining kinematical data of their inner regions with global observational properties, the Universal Rotation Curve (URC) of disk galaxies and the corresponding mass distribution out to their virial radius. This curve extends the results of Paper I, concerning the inner luminous regions of Sb-Im spirals, out to the edge of the galaxy halos.Comment: In press on MNRAS. 10 pages, 8 figures. The Mathematica code for the figures is available at: http://www.novicosmo.org/salucci.asp Corrected typo

O extrativismo da castanha-do-brasil na região do Baixo Rio Branco, RR.

bitstream/item/36945/1/39.pd

Variações anuais na produção de frutos e sementes de Castanheira-do-Brasil (Bertholletia excelsa Bonpl., Lecythidaceae) em florestas nativas de Roraima.

Este trabalho foi desenvolvido com o objetivo de estudar as variações anuais na produção de frutos e sementes entre populações e indivíduos em castanhais nativos de Roraima. Os dados foram obtidos em cinco parcelas permanentes de 300 m x 300 m instaladas nos Municípios de Caracaraí e São João da Baliza. Nas parcelas permanentes, todas as castanheiras com diâmetro à altura do peito (DAP) superior ou igual a 10 cm foram identificadas, medidas e numeradas através de placas de alumínio presas aos fustes por pregos. Durante o período de queda dos frutos (março a julho), as árvores foram visitadas em duas ocasiões no meio e no final desse período, e os frutos contados, abertos e pesados com balança de gancho digital com precisão de 50 g. A produção de frutos e sementes varia entre populações e indivíduos e a maioria não produz frutos todos os anos. No ano de maior produção, um castanhal chega a produzir 52 vezes mais do que em anos de baixa. Nos locais estudados, a produção total concentra-se em um pequeno número de indivíduos com um ano de pico de produção (mast-year)

EU Dairy Sector: Impact of Luxemburg Reform, EU Enlargement and Trade Negotiations

The EU dairy sector is facing a period of significant changes that are due to three major decisions: the EU enlargement, the Luxembourg reform and on-going WTO negotiations. To evaluate the impact of such changes we developed a model of the EU and world dairy industry. The model is composed of two modules that interact: a milk and beef supply module and a dairy industry module. In this paper we present the model and focus on elements that are crucial for a better understanding of the impact of reforms: quota rents in the EU, evolution of production in the new member states and trade policy.agricultural policy, dairy industry, partial equilibrium model, International Relations/Trade, C21, Q13, Q18,

The Disk Mass of Spiral Galaxies

We derive the disk masses of 18 spiral galaxies of different luminosity and Hubble Type, both by mass modelling their rotation curves and by fitting their SED with spectro-photometric models. The good agreement of the estimates obtained from these two different methods allows us to quantify the reliability of their performance and to derive very accurate stellar mass-to-light ratio vs color (and stellar mass) relationships.Comment: 5 pages, 4 Figures accepted to M