Measuring Volatility in Dairy Commodity Prices

The policy environment facing the EU dairy industry continues to undergo considerable change under WTO and CAP reform. Movement away from supply management by the EU and a more liberal global agricultural trading system will involve greater price volatility for dairy commodities. It is anticipated that EU dairy prices will more closely align with world prices. World prices are both lower and more volatile than EU prices and it is further assumed that this increased volatility will be transmitted to EU prices. Price volatility is a concern for a number of reasons as it adds challenges for business planning, debt repayment, and, in some cases, solvency. Representative EU and world butter and SMP (Skim Milk Powder) prices are considered and using the ARMA and GARCH framework their volatility is quantified.Price Volatility, ARMA, GARCH, Butter, SMP, Dairy Policy, Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety,

Managing Price Risk in a Changing Policy Environment: The Case of the EU Dairy Industry

The EU dairy industry faces an unprecedented level of change. The anticipated removal of milk quotas and the move to a less restricted global trade environment will provide the industry with both opportunities and challenges. The primary challenge will be the need for the industry to deal with more volatile prices. Active management of the risks associated with these more volatile prices will help to place the industry in a more competitive position. However this will require the industry and policy makers to embrace a new set of tools. For example the US dairy industry has been much more active in the management of risk and lessons from their experience provide a valuable insight into which tools may be more appropriate in an EU context.Dairy, Risk Management, EU, US,

The First Moment of Azimuthal Anisotropy in Nuclear Collisions from AGS to LHC Energies

We review topics related to the first moment of azimuthal anisotropy ($v_1$), commonly known as directed flow, focusing on both charged particles and identified particles from heavy-ion collisions. Beam energies from the highest available, at the CERN LHC, down to projectile kinetic energies per nucleon of a few GeV per nucleon, as studied in experiments at the Brookhaven AGS, fall within our scope. We focus on experimental measurements and on theoretical work where direct comparisons with experiment have been emphasized. The physics addressed or potentially addressed by this review topic includes the study of Quark Gluon Plasma, and more generally, investigation of the Quantum Chromodynamics phase diagram and the equation of state describing the accessible phases.Comment: Accepted for publication in Advances in High Energy Physic

Measurement of the Effect of Policy Changes on Volatility in Dairy Markets1

Volatility in dairy commodity markets has become a major concern for many in the dairy supply chain and is likely to remain so in the future. Changes to the Common Agricultural Policy (CAP) over the past decade have more closely aligned EU and World prices and their associated volatilities. The aim of this paper is to measure volatility at farm level in Ireland over time, identify possible reasons for the increased volatility and identify ways of reducing volatility. Statistical measures such as coefficient of variation (CV) and annualised standard deviation are used to provide measures of past volatility and its evolution over time. Family Farm Income (FFI) data, input data and farm gate milk prices are used to highlight historical farm level volatility. As farm level prices should be based on dairy commodity returns, the links between these prices and the farm gate prices are explored. Monthly wholesale prices for Skim Milk Powder (SMP), whole milk powder (WMP), and butter between January 1997 and March 2012 are used for this analysis. The time period is divided into two sub periods to quantify changes in volatility pre and post the Luxembourg Agreement. The results highlight that both commodity price and farm gate volatility has increased dramatically post 2007. Volatility will become a more inherent part of the dairy industry as policy changes cause prices to become further aligned with world prices. The findings of this research highlight that risk management strategies are desirable for the long term success of the dairy industry

Nuclear transport models can reproduce charged-particle-inclusive measurements but are not strongly constrained by them

Nuclear transport models are important tools for interpretation of many heavy-ion experiments and are essential in efforts to probe the nuclear equation of state. In order to fulfill these roles, the model predictions should at least agree with observed single-particle-inclusive momentum spectra; however, this agreement has recently been questioned. The present work compares the Vlasov-Uehling-Uhlenbeck model to data for mass-symmetric systems ranging from 12C+12C to 139La+139La, and we find good agreement within experimental uncertainties at 0.4A and 0.8A GeV. For currently available data, these uncertainties are too large to permit effective nucleon-nucleon scattering cross sections in the nuclear medium to be extracted at a useful level of precision

Recalibration of the binding energy of hypernuclei measured in emulsion experiments and its implications

The $\Lambda$ separation energy for $\Lambda$-hypernuclei, denoted $B_\Lambda$, measured in 1967, 1968, and 1973 are recalibrated using the current best mass estimates for particles and nuclei. The recalibrated $B_\Lambda$ are systematically larger (except in the case of $^6_\Lambda$He) than the original published values by about 100 keV. The effect of this level of recalibration is very important for light hypernuclei, especially for the hypertriton. The early $B_\Lambda$ values measured in 1967, 1968, and 1973 are widely used in theoretical research, and the new results provide better constraints on the conclusions from such studies.Comment: To be published in Chinese Physics

Comparison of Vlasov-Uehling-Uhlenbeck model with 4 π Heavy Ion Data

Streamer chamber data for collisions of Ar + KCl and Ar + BaI2 at 1.2 GeV/nucleon are compared with microscopic model predictions based on the Vlasov-Uehling-Uhlenbeck equation, for various density-dependent nuclear equations of state. Multiplicity distributions and inclusive rapidity and transverse momentum spectra are in good agreement. Rapidity spectra show evidence of being useful in determining whether the model uses the correct cross sections for binary collisions in the nuclear medium, and whether momentum-dependent interactions are correctly incorporated. Sideward flow results do not favor the same nuclear stiffness parameter at all multiplicities

Measurement of collective flow in heavy ion collisions using particle pair correlations

We present a new type of flow analysis, based on a particle-pair correlation function, in which there is no need for an event-by-event determination of the reaction plane. Consequently, the need to correct for dispersion in an estimated reaction plane does not arise. Our method also offers the option to avoid any influence from particle misidentification. Using this method, streamer chamber data for collisions of Ar+KCl and Ar+BaI2 at 1.2 GeV/nucleon are compared with predictions of a nuclear transport model

Comparison of nuclear transport models with 800A-MeV La + La data

Nuclear transport models including density- and momentum-dependent mean-field effects are compared to intranuclear-cascade models and tested on recent data on inclusive p-like cross sections for 800A-MeV La+La. We find a remarkable agreement between most model calculations but a systematic disagreement with the measured yield at 20°, possibly indicating a need for modification of nuclear transport properties at high densities