1,528 research outputs found
A Comparison of Intercountry Agricultural Production Functions: A Frontier Function Approach
Unlike the work by Hayami and Ruttan in the 1970s, this study utilizes frontier meta- production functions to study intercountry agricultural productivity differences. Technical efficiency differences are examined through estimation of deterministic and stochastic frontiers for 43 countries over 1960, 1970 and 1980. In most cases, developed countries on average have higher technical efficiency levels. However, not all developed countries are fully technically efficient while certain developing countries perform comparably with other developed countries. The results also show that the productivity gap between developing and developed countries has increased over time. Yet there is potential to improve productivity of developing countries, especially by expanding their human capital stock, as indicated by high output elasticities for primary and secondary education and technical education.
Effect of Trade Liberalization in the Short-Grain Japonica Rice Market: A Spatial-Temporal Equilibrium analysis
Serious attention has always been bestowed on the stability of food markets. The government has acted on these issues through intervention on food prices that more or less creates distortion. These have been observed on U.S. and Japan. This paper develops a spatial-temporal equilibrium model for short-grain japonica trade and simulates policy alternatives for free trade and improved trade. It then discusses the results and its implications on the Philippine economy.demand
A CAUTIONARY NOTE ON POLYNOMIAL DISTRIBUTED LAG FORMULATIONS OF SUPPLY RESPONSE
This paper uses the Pagano-Hartley procedure to estimate the lag length and polynomial degree for the case of a quarterly hog supply equation. The results show that the nicely humped shapes which materialize when using the Almon lag may be caused by the failure in accounting for autocorrelation in determining lag length and polynominal degree.Livestock Production/Industries, Research Methods/ Statistical Methods,
Variations on Supersymmetry Breaking and Neutrino Spectra
The problem of generating light neutrinos within supersymmetric models is
discussed. It is shown that the hierarchy of scales induced by supersymmetry
breaking can give rise to suppression factors of the correct order of magnitude
to produce experimentally allowed neutrino spectra.Comment: 18 pages, LaTeX, Contribution to "Neutrino Workshop", Fuji-Yoshida,
Japan, August 200
Search for doubly charged Higgs bosons using the same-sign diboson mode at the LHC
Doubly charged Higgs bosons are predicted in many new physics models with an
extended Higgs sector that contains a Higgs triplet field. Current experimental
searches have been focusing mainly on the scenario in which the same-sign
dilepton decay modes are the dominant ones. We study the scenario where the
vacuum expectation value of the triplet field is sufficiently large so that the
associated charged Higgs bosons decay dominantly to a pair of weak gauge bosons
instead. A detailed simulation of the signal and the backgrounds is performed
for the CERN Large Hadron Collider at the collision energy of 8 TeV and 14 TeV.
We find that different cuts should be imposed for the events, depending on
whether the doubly charged Higgs boson mass is greater than about 200 GeV. In
the higher mass region, the forward jet tagging proves to be useful in
enhancing the signal significance. We show the discovery reach of the LHC
running at 8 and 14 TeV, with two benchmark triplet vacuum expectation values.
With an integrated luminosity of 10 fb at 8 TeV, the doubly charged
Higgs boson with a mass of GeV can be tested at level in
such a scenario.Comment: 18 pages, 10 figures; published in Physical Review
A 125GeV Higgs Boson and Muon g-2 in More Generic Gauge Mediation
Recently, the ATLAS and CMS collaborations reported exciting hints of a
Standard Model-like Higgs boson with a mass around 125GeV. A Higgs boson this
heavy is difficult to realize in conventional models of gauge mediation. Here
we revisit the lightest Higgs boson mass in "more generic gauge mediation,"
where the Higgs doublets mix with the messenger doublets. We show that a Higgs
boson mass around 125GeV can be realized in more generic gauge mediation
models, even for a relatively light gluino mass ~1TeV. We also show that the
muon anomalous magnetic moment can be within 1sigma of the experimental value
for these models, even when the Higgs boson is relatively heavy. We also
discuss the LHC constraints and the prospects of discovery.Comment: 28 pages, 7 figures. Corrections and references are adde
Leptogenesis after Chaotic Sneutrino Inflation and the Supersymmetry Breaking Scale
We discuss resonant leptogenesis arising from the decays of two
nearly-degenerate right-handed neutrinos, identified as the inflaton and
stabiliser superfields in a model of chaotic sneutrino inflation. We compare an
analytical estimate of the baryon asymmetry in the Boltzmann
approximation to a numerical solution of the full density matrix equations, and
find that the analytical result fails to capture the correct physics in certain
regions of parameter space. The observed baryon asymmetry can be realised for a
breaking of the mass degeneracy as small as . The
origin of such a small mass splitting is explained by considering supersymmetry
(SUSY) breaking in supergravity, which requires a constant in the
superpotential of the order of the gravitino mass to cancel the
cosmological constant. This yields additional terms in the (s)neutrino mass
matrices, lifting the degeneracy and linking to the SUSY breaking
scale. We find that achieving the correct baryon asymmetry requires a gravitino
mass TeV.Comment: v2: 25 pages, 4 figures; version published in NPB, minor corrections.
v1: 24 pages, 4 figure
Novel Supersymmetric SO(10) Seesaw Mechanism
We propose a new seesaw mechanism for neutrino masses within a class of
supersymmetric SO(10) models with broken D-parity. It is shown that in such
scenarios the B-L scale can be as low as TeV without generating inconsistencies
with gauge coupling unification nor with the required magnitude of the light
neutrino masses. This leads to a possibly light new neutral gauge boson as well
as relatively light quasi-Dirac heavy leptons. These particles could be at the
TeV scale and mediate lepton flavour and CP violating processes at appreciable
levels.Comment: 4 pages, 3 figures, revtex4, references added, typos corrected,
sharper discussion of the RGEs give
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