10,799 research outputs found
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,
Local Polynomial Fitting and Spatial Price Relationships: Price Transmission in the EU Markets for Pigmeat
We apply nonparametric methods to assess price transmission processes within the EU pig markets. We compare results derived from nonparametric regressions with those obtained using alternative nonlinear threshold models. Results show that nonparametric regressions support the parametric results. However, parametric techniques often suggest a higher degree of price transmission than that implied by threshold models.Livestock Production/Industries, Marketing,
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,
Configurations and relative efficiencies of shrimp trawls employed in southeastern United States waters
Common shrimp trawl designs employed in the southeastern United States shrimp fishery are the flat, balloon, semiballoon, jib, and super X-3. Recent innovations in trawl design and rigging, including the twin trawl rigging and tongue trawl design, have improved the efficiency of shrimp trawling gear. A description of the construction techniques for the different designs indicate differences which affect gear performance. Measurements of horizontal spread and vertical opening for 76 trawl configurations indicate the relative efficiencies of the different designs. Maximum horizontal spreading efficiency was achieved by the "twin" and "tongue" trawl designs followed by the super X-3, jib, balloon, and semiballoon designs. Designs having the greatest vertical openings were the tongue and flat trawl designs followed by the semiballoon. Maximum total gape dimension was demonstrated by the "Mongoose" tongue trawl. Comparison of trawl spreading efficiency and door area to headrope length ratio indicates that a range of 70-80 in square (per door) of door area is required for each foot of trawl headrope length for maximum efficiency with conventional trawl designs and 66-75 in square per foot of headrope for tongue trawl designs. (PDF file contains 18 pages.
Physical Properties of Galactic Planck Cold Cores revealed by the Hi-GAL survey
Previous studies of the initial conditions of massive star formation have
mainly targeted Infrared-Dark Clouds (IRDCs) toward the inner Galaxy. This is
due to the fact that IRDCs were first detected in absorption against the bright
mid-IR background, requiring a favourable location to be observed. By
selection, IRDCs represent only a fraction of the Galactic clouds capable of
forming massive stars and star clusters. Due to their low dust temperatures,
IRDCs are bright in the far-IR and millimeter and thus, observations at these
wavelengths have the potential to provide a complete sample of star-forming
massive clouds across the Galaxy. Our aim is to identify the clouds at the
initial conditions of massive star formation across the Galaxy and compare
their physical properties as a function of their Galactic location. We have
examined the physical properties of a homogeneous galactic cold core sample
obtained with the Planck satellite across the Galactic Plane. With the use of
Herschel Hi-GAL observations, we have characterized the internal structure of
them. By using background-subtracted Herschel images, we have derived the H2
column density and dust temperature maps for 48 Planck clumps. Their basic
physical parameters have been calculated and analyzed as a function of location
within the Galaxy. These properties have also been compared with the empirical
relation for massive star formation derived by Kauffmann & Pillai (2010). Most
of the Planck clumps contain signs of star formation. About 25% of them are
massive enough to form high mass stars. Planck clumps toward the Galactic
center region show higher peak column densities and higher average dust
temperatures than those of the clumps in the outer Galaxy. Although we only
have seven clumps without associated YSOs, the Hi-GAL data show no apparent
differences in the properties of Planck cold clumps with and without star
formation.Comment: 22 pages, 11 figures, accepted for publication in A&
Star formation associated with neutral hydrogen in the outskirts of early-type galaxies
About 20 percent of all nearby early-type galaxies ( M) outside the Virgo cluster are surrounded by a disc
or ring of low-column-density neutral hydrogen (HI) gas with typical radii of
tens of kpc, much larger than the stellar body. In order to understand the
impact of these gas reservoirs on the host galaxies, we analyse the
distribution of star formation out to large radii as a function of HI
properties using GALEX UV and SDSS optical images. Our sample consists of 18
HI-rich galaxies as well as 55 control galaxies where no HI has been detected.
In half of the HI-rich galaxies the radial UV profile changes slope at the
position of the HI radial profile peak. To study the stellar populations, we
calculate the FUV-NUV and UV-optical colours in two apertures, 1-3 and 3-10
R . We find that HI -rich galaxies are on average 0.5 and 0.8 mag bluer
than the HI-poor ones, respectively. This indicates that a significant fraction
of the UV emission traces recent star formation and is associated with the HI
gas. Using FUV emission as a proxy for star formation, we estimate the
integrated star formation rate in the outer regions (R > 1R) to be on
average M yr for the HI-rich galaxies. This
rate is too low to build a substantial stellar disc and, therefore, change the
morphology of the host. We find that the star formation efficiency and the gas
depletion time are similar to those at the outskirts of spirals.Comment: 27 pages (13 without appendices). 9 figures, 5 tables, 2 appendix
tables and 12 appendix figures. Accepted for publication in MNRA
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