5,557 research outputs found

    Wheat Forward Contract Pricing: Evidence on Forecast Power and Risk Premia

    Get PDF
    While the risk premium hypothesis in futures markets has been the subject of a long and continuous controversy, the risk premium hypothesis in forward markets is also of interest among economists. The hypothesis is supported by some theoretical arguments and empirical evidence yet remains an open question. We in this study apply a two-equation regression model similar to those used in (Fama and French (1987} and de Roon et al. (1998) to analyze the risk premiums in forward markets, particularly, using the pre-harvest wheat forward markets in Illinois (1982-2004) and Kansas (1990-2004) as an example. The two-equation regression model consists of a forecasting equation, which uses a forward basis during a pre-harvest period to forecast the spot basis at the following harvest period, and a risk premium equation, which uses the forward basis to predict the risk premium to be realized at the harvest. The empirical results show that, first, the average realized risk premiums for Illinois fluctuate around a level during the entirety of a pre-harvest period, while the risk premiums for Kansas show a slight downward trend as time approaches the harvest. The average realized risk premiums are generally positive and bigger for Illinois than for Kansas, but all mean risk premiums are within one units of their corresponding standard deviations. Second, the pre-harvest forward bases have reliable forecasting power for the spot harvest bases and contain information regarding the risk premiums, which strongly recommend estimating risk premiums conditional on forward bases.Marketing,

    The Marketing Performance of Illinois and Kansas Wheat Farmers

    Get PDF
    The purpose of this paper is to analyze the marketing performance of wheat farmers in Illinois and Kansas over 1982–2004. The results show that farmer benchmark prices for wheat in Illinois and Kansas fall in the middle third of the price range about half to three-quarters of the time. Consistent with previous studies, this refutes the contention that Illinois and Kansas wheat farmers routinely market the bulk of their wheat crop in the bottom portion of the price range. Tests of the average difference between farmer and market benchmark prices are sensitive to the market benchmark considered. The marketing performance of wheat farmers in Illinois and Kansas is about equal to the market if a 24- or 20-month market benchmark is used, slightly above the market if a 12-month price benchmark is used, and significantly less than the market if the harvest benchmark is used. The sensitivity of marketing performance to the market benchmark considered is explained by the seasonal pattern of prices. While Illinois producers performed slightly better than their counterparts in Kansas, notable differences in performance across these two geographic areas is not observed.benchmarks, Illinois, Kansas, marketing, performance, price, wheat, Agribusiness, Crop Production/Industries, Marketing, Production Economics, Productivity Analysis, Q11, Q13,

    Exceptional Points in a Microwave Billiard with Time-Reversal Invariance Violation

    Get PDF
    We report on the experimental study of an exceptional point (EP) in a dissipative microwave billiard with induced time-reversal invariance (T) violation. The associated two-state Hamiltonian is non-Hermitian and non-symmetric. It is determined experimentally on a narrow grid in a parameter plane around the EP. At the EP the size of T violation is given by the relative phase of the eigenvector components. The eigenvectors are adiabatically transported around the EP, whereupon they gather geometric phases and in addition geometric amplitudes different from unity

    Lifshitz and Excited State Quantum Phase Transitions in Microwave Dirac Billiards

    Full text link
    We present experimental results for the density of states (DOS) of a superconducting microwave Dirac billiard which serves as an idealized model for the electronic properties of graphene. The DOS exhibits two sharp peaks which evolve into van Hove singularities with increasing system size. They divide the band structure into regions governed by the \emph{relativistic} Dirac equation and by the \emph{non-relativistic} Schr\"odinger equation, respectively. We demonstrate that in the thermodynamic limit a topological transition appears as a neck-disrupting Lifshitz transition in the number susceptibility and as an excited state transition in the electronic excitations. Furthermore, we recover the finite-size scaling typical for excited state quantum phase transitions involving logarithmic divergences and identify a quasi-order parameter

    Generalized Taub-NUT metrics and Killing-Yano tensors

    Get PDF
    A necessary condition that a St\"ackel-Killing tensor of valence 2 be the contracted product of a Killing-Yano tensor of valence 2 with itself is re-derived for a Riemannian manifold. This condition is applied to the generalized Euclidean Taub-NUT metrics which admit a Kepler type symmetry. It is shown that in general the St\"ackel-Killing tensors involved in the Runge-Lenz vector cannot be expressed as a product of Killing-Yano tensors. The only exception is the original Taub-NUT metric.Comment: 14 pages, LaTeX. Final version to appear in J.Phys.A:Math.Ge
    • 

    corecore