442 research outputs found
Impact of Changes in Dietary Preferences on U.S. Retail Demand for Beef: Health Concerns and the Role of Media
The goal of this study is twofold: to determine if in the long run health concerns affect, via changes in consumer dietary preferences, the retail demand for beef in the United States and to establish if media coverage of popular diets (media frenzy) causes the change in retail demand for beef, or if it simply reports the facts about the changes in consumer dietary preferences. Data used in the analysis are the quarterly retail demand index for beef and the number of newspaper articles and magazine features on low-fat, low-cholesterol and low-carb diets published in the United States between 1990:I and 2004:IV. Johansen's cointegration method and vector error correction (VEC) model based Granger causality test were used in the long-run and short-run analysis respectively. The results indicate that health concerns are an important demand shifter for beef in the long run. In the short run, media serves as a trigger that will swing people to become followers of a certain diet.Health concerns, media, demand for beef, cointegration, VEC, Granger causality, Food Consumption/Nutrition/Food Safety, D12, Q13,
Testing CDM at the lowest redshifts with SN Ia and galaxy velocities
Peculiar velocities of objects in the nearby universe are correlated due to
the gravitational pull of large-scale structure. By measuring these velocities,
we have a unique opportunity to test the cosmological model at the lowest
redshifts. We perform this test, using current data to constrain the amplitude
of the "signal" covariance matrix describing the velocities and their
correlations. We consider a new, well-calibrated "Supercal" set of low-redshift
SNe Ia as well as a set of distances derived from the fundamental plane
relation of 6dFGS galaxies. Analyzing the SN and galaxy data separately, both
results are consistent with the peculiar velocity signal of our fiducial
CDM model, ruling out the noise-only model with zero peculiar
velocities at greater than (SNe) and (galaxies). When the
two data sets are combined appropriately, the precision of the test increases
slightly, resulting in a constraint on the signal amplitude of , where corresponds to our fiducial model.
Equivalently, we report an 11% measurement of the product of the growth rate
and amplitude of mass fluctuations evaluated at , , valid for our fiducial CDM model.
We explore the robustness of the results to a number of conceivable variations
in the analysis and find that individual variations shift the preferred signal
amplitude by less than . We briefly discuss our Supercal SN Ia
results in comparison with our previous results using the JLA compilation.Comment: 21 pages, 5 figures, minor changes to match the published versio
CONSIDERATIONS ON THE PLANNING OF THE FINANCIAL AUDIT MISSION
In order to exercise efficiently the financial audit it is required to adequately plan it, for each individual mission. This document synthesizes the essential aspects which must be taken into account by the auditors and divides them into groups, according to the following paths of action: obtaining a detailed knowledge of the entity audited; estimating an acceptable level of the audit risk; understanding the internal control system of the entity; determining rigorously of the terms of the mission.audit, planning, particularities, risk, engagement
Cosmology from supernova magnification maps
High-z Type Ia supernovae are expected to be gravitationally lensed by the
foreground distribution of large-scale structure. The resulting magnification
of supernovae is statistically measurable, and the angular correlation of the
magnification pattern directly probes the integrated mass density along the
line of sight. Measurements of cosmic magnification of supernovae therefore
complements galaxy shear measurements in providing a direct measure of
clustering of the dark matter. As the number of supernovae is typically much
smaller than the number of sheared galaxies, the two-point correlation function
of lensed Type Ia supernovae suffers from significantly increased shot noise.
Neverthless, we find that the magnification map of a large sample of
supernovae, such as that expected from next generation dedicated searches, will
be easily measurable and provide an important cosmological tool. For example, a
search over 20 sq. deg. over five years leading to a sample of ~ 10,000
supernovae would measure the angular power spectrum of cosmic magnification
with a cumulative signal-to-noise ratio of ~20. This detection can be further
improved once the supernova distance measurements are cross-correlated with
measurements of the foreground galaxy distribution. The magnification maps made
using supernovae can be used for important cross-checks with traditional
lensing shear statistics obtained in the same fields, as well as help to
control systematics. We discuss two applications of supernova magnification
maps: the breaking of the mass-sheet degeneracy when estimating masses of
shear-detected clusters, and constraining the second-order corrections to weak
lensing observables.Comment: 4 pages, 2 figures, ApJL submitted; "Signal" discussed here is the
extra covariance in astro-ph/050958
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