16,528 research outputs found
Safety Nets or Trampolines? Federal Crop Insurance, Disaster Assistance, and the Farm Bill
We review the implications of the 2007 Farm Bill for the risk management dimensions of U.S. agriculture and policy. Legislative proposals suggest significant changes in risk management policy, including the introduction of state or national revenue insurance. We also pursue an empirical analysis of the interrelationships of crop insurance, disaster relief, and farm profitability. We find an inverse relationship between disaster assistance and insurance purchases. Our analysis also suggests that farmers that buy insurance and that receive disaster payments tend to have higher returns to farming.crop insurance, disaster payments, Farm Bill, Agribusiness, Agricultural and Food Policy, Crop Production/Industries, Risk and Uncertainty, Q18,
MODELING CHANGES IN THE U.S. DEMAND FOR CROP INSURANCE DURING THE 1990S
The crop insurance purchase decision for a group of Kansas farmers is analyzed using data from 1990sa period that experienced many changes in the federal crop insurance program. Farm-level data are used. Results indicate a reduction in the elasticity of the demand for crop insurance with respect to premium rates by the end of the decade. This corresponded with a considerable increase in government subsidies by the end of the 1990s. This may also reflect the attractiveness of new revenue insurance products that may have made producers less sensitive to premium changes.Risk and Uncertainty,
Palliative care: promoting general practice participation
Specialist palliative care services and services involved in the pre-palliative phase of a patient’s disease must accept GPs as an integral part of the care tea
Farmers' Crop Acreage Decisions in the Presence of Credit Constraints: Do Decoupled Payments Matter?
While in theory decoupled payments do not distort production decisions, in practice there are several potential coupling mechanisms for these payments. We use farm-level data from Kansas to revisit the issue of how (de)coupled are these supposedly “decoupled” payments by focusing on how they may impact production through credit constraints. In particular, we study how production effects may have differed across farmers with varying levels of debt pressure. Our empirical approach exploits the fact that we can observe the same farm over time (and so can account for the effects of time-constant omitted variables) to study how these payments affected total crop acres, owned acres, and the decisions to plant corn, sorghum, soybeans and wheat. Like previous studies, we find small production effects. Nonetheless our results suggest decoupled payments have potentially distortionary effects on production.decoupled payments, credit constraints, Agricultural Finance, Q17, Q18,
Surface Polar Phonon Dominated Electron Transport in Graphene
The effects of surface polar phonons on electronic transport properties of
monolayer graphene are studied by using a Monte Carlo simulation. Specifically,
the low-field electron mobility and saturation velocity are examined for
different substrates (SiC, SiO2, and HfO2) in comparison to the intrinsic case.
While the results show that the low-field mobility can be substantially reduced
by the introduction of surface polar phonon scattering, corresponding
degradation of the saturation velocity is not observed for all three substrates
at room temperature. It is also found that surface polar phonons can influence
graphene electrical resistivity even at low temperature, leading potentially to
inaccurate estimation of the acoustic phonon deformation potential constant
Effects of Decoupling on the Average and the Variability of Output
Previous research has ignored the influence of inputs on output risk when assessing the effects of decoupled income-support payments on production decisions. This paper studies the impacts of agricultural policy decoupling on output variability and mean by explicitly considering the influence of agricultural input use on the stochastic component of production. We develop a theoretical framework that studies production responses of agricultural producers to apparently decoupled payments. Results show that, under DARA preferences, government transfers will have the effect of increasing production risk. Inferences on the effects of payments on output mean are also made. In our empirical application we use farm-level data collected in Kansas to illustrate the model.decoupling, output risk, risk preferences, Just-Pope production function, Demand and Price Analysis, Q12, Q18,
Decoupling farm policies: how does this affect production?
This paper studies the extent to which decoupled income support measures in agriculture can have production implications both at the extensive and intensive margins. We develop a theoretical framework that analyzes production responses of agricultural producers to apparently decoupled payments, by explicitly considering risk attitudes and uncertainty. We use farm-level data collected in Kansas to estimate the model. Technology and risk preference parameters are jointly estimated. Results show that though lump sum payments are not fully decoupled in the presence of risk and uncertainty, their effects on agricultural production are likely to be of a very small magnitude.Agricultural and Food Policy,
Electron Spin Relaxation under Drift in GaAs
Based on a Monte Carlo method, we investigate the influence of transport
conditions on the electron spin relaxation in GaAs. The decay of initial
electron spin polarization is calculated as a function of distance under the
presence of moderate drift fields and/or non-zero injection energies. For
relatively low fields (a couple of kV/cm), a substantial amount of spin
polarization is preserved for several microns at 300 K. However, it is also
found that the spin relaxation rate increases rapidly with the drift field,
scaling as the square of the electron wavevector in the direction of the field.
When the electrons are injected with a high energy, a pronounced decrease is
observed in the spin relaxation length due to an initial increase in the spin
precession frequency. Hence, high-field or high-energy transport conditions may
not be desirable for spin-based devices.Comment: 4 pages, 3 figures, one table. Scheduled for publication in the May
26, 2003 issue of Applied Physics Letters (039321APL
First Principles Analysis of Electron-Phonon Interaction in Graphene
The electron-phonon interaction in monolayer graphene is investigated by
using density functional perturbation theory. The results indicate that the
electron-phonon interaction strength is of comparable magnitude for all four
in-plane phonon branches and must be considered simultaneously. Moreover, the
calculated scattering rates suggest an acoustic phonon contribution that is
much weaker than previously thought, revealing the role of optical phonons even
at low energies. Accordingly it is predicted, in good agreement with a recent
measurement, that the intrinsic mobility of graphene may be more than an order
of magnitude larger than the high values reported in suspended samples.Comment: 12 pages, 4 figure
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