A Stochastic Analysis of Proposals for the New US Farm Bill

Most of the large scale modeling systems used in the analysis of agricultural policies produce deterministic projections. In reality, however, the agricultural sector is subject to a high degree of uncertainty as a result of fluctuations in exogenous factors such as the weather or macroeconomic variation. A stochastic approach can provide additional information to policy makers regarding the implications of this uncertainty, through the use of stochastically generated projections. This paper also shows how deterministic analysis may result in systematic errors in the projection of some variables. As an applied example, the FAPRI model of the US agricultural sector is simulated stochastically to analyse the impact of proposals for the new US farm bill.Stochastic simulation, US Farm Bill, policy analysis, Agricultural and Food Policy,

Игровые технологии на английском языке в курсе "Микроэкономика"

В современных условиях профессиональная подготовка специалиста требует знание иностранного языка на уровне, позволяющем свободно общаться, читать, находить необходимую информацию. В статье анализируется игра как активный метод обучения, позволяющая реализовать иноязычную коммуникативную компетенцию в курсе"Микроэкономика"

Probing Yukawa Unification with K and B Mixing

We consider corrections to the unification of down-quark and charged-lepton Yukawa couplings in supersymmetric GUTs, which links the large nu_tau-nu_mu mixing angle to b -> s transitions. These corrections generically occur in simple grand-unified models with small Higgs representations and affect s -> d and b -> d transitions via the mixing of the corresponding right-handed superpartners. On the basis of a specific SUSY-SO(10) model, we analyze the constraints from K-Kbar and B-Bbar mixing on the additional \tilde{d}_R-\tilde{s}_R rotation angle theta. We find that epsilon_K already sets a stringent bound on theta, theta^{max}=O(1 degree), indicating a very specific flavor structure of the correction operators. The impact of the large neutrino mixings on the unitarity triangle analysis is also briefly discussed, as well as their ability to account for the sizeable CP-violating phase observed recently in B_s -> psi phi decays.Comment: 19 pages. Discussion in Sec. 5.2 slightly extended; minor numerical modifications in Secs. 5.1 to 5.4, conclusions unchanged. Version to appear in JHE

Phase-Locked Spatial Domains and Bloch Domain Walls in Type-II Optical Parametric Oscillators

We study the role of transverse spatial degrees of freedom in the dynamics of signal-idler phase locked states in type-II Optical Parametric Oscillators. Phase locking stems from signal-idler polarization coupling which arises if the cavity birefringence and/or dichroism is not matched to the nonlinear crystal birefringence. Spontaneous Bloch domain wall formation is theoretically predicted and numerically studied. Bloch walls connect, by means of a polarization transformation, homogeneous regions of self-phase locked solutions. The parameter range for their existence is analytically found. The polarization properties and the dynamics of walls in one- and two transverse spatial dimensions is explained. Transition from Bloch to Ising walls is characterized, the control parameter being the linear coupling strength. Wall dynamics governs spatiotemporal dynamical states of the system, which include transient curvature driven domain growth, persistent dynamics dominated by spiraling defects for Bloch walls, and labyrinthine pattern formation for Ising walls.Comment: 27 pages, 16 figure

FAPRI 2001 U.S. and World Agricultural Outlook

Crop Production/Industries, Livestock Production/Industries,

Rare B decays and Tevatron top-pair asymmetry

The recent Tevatron result on the top quark forward-backward asymmetry, which deviates from its standard model prediction by 3.4$\sigma$, has prompted many authors to build new models to account for this anomaly. Among the various proposals, we find that those mechanisms which produce $t\bar t$ via $t$- or $u$-channel can have a strong correlation to the rare B decays. We demonstrate this link by studying a model with a new charged gauge boson, $W'$. In terms of the current measurements on $B\to \pi K$ decays, we conclude that the branching ratio for $B^-\to \pi^- \bar K^0$ is affected most by the new effects. Furthermore, using the world average branching ratio for the exclusive B decays at $2\sigma$ level, we discuss the allowed values for the new parameters. Finally, we point out that the influence of the new physics effects on the direct CP asymmetry in B decays is insignificant.Comment: 15 page, 6 figures, typos corrected and references added, final version to appear journa

FAPRI 2002 World Agricultural Outlook

Crop Production/Industries, Livestock Production/Industries,

FAPRI 2001 U.S. Baseline Briefing Book

This document is a baseline projection for the agricultural economy using a very specific set of assumptions. The baseline serves as a benchmark for analyzing alternative policies.Material in this publication is based upon work supported by the Cooperative State Research, Education and Extension Service, U.S. Department of Agriculture, under Agreement No. 99-34149-7373

Virtual signatures of dark sectors in Higgs couplings

Where collider searches for resonant invisible particles loose steam, dark sectors might leave their trace as virtual effects in precision observables. Here we explore this option in the framework of Higgs portal models, where a sector of dark fermions interacts with the standard model through a strong renormalizable coupling to the Higgs boson. We show that precise measurements of Higgs-gauge and triple Higgs interactions can probe dark fermions up to the TeV scale through virtual corrections. Observation prospects at the LHC and future lepton colliders are discussed for the so-called singlet-doublet model of Majorana fermions, a generalization of the bino-higgsino scenario in supersymmetry. We advocate a two-fold search strategy for dark sectors through direct and indirect observables.Comment: 20 pages, 7 figures, 1 tabl