50,646 research outputs found
Commodity Markets: Rational Expectations in Markets With Irrational Investors
The "financialization" of commodity markets have become a concern for policy makers and market participants. What was once a market for the hedging of holding physical commodities has expanded to become a market for the diversification of financial assets. When financial assets diversification goals are decoupled from the fundamental factors that affect producers and consumers of physical goods futures markets may not be as efficient in aggregating information concerning the economics of the underlying commodity. Theoretical understanding of whether commodity futures market function well under exogenous shifts in demand for futures contracts depend on our assumptions of how market participants behave, including their level of risk aversion. This paper builds a competitive storage model with an explicit futures market that incorporates irrational shocks to demand for futures contracts. This model is flexible enough to investigate the impact of the "financialization" of commodity futures markets and the resulting impacts.commodity, futures, financialization, competitive storage, rational expectations, Agricultural and Food Policy, Agricultural Finance, Financial Economics, Risk and Uncertainty,
A meta-narrative review of electronic patient records
This session comprises four papers that consider how systematic review methods may be
developed in order to make the best use of complex evidence in education and health.
The methods and approaches reflected upon in these papers are not drawn from a single
research tradition, but share a common goal of broadening the methodological scope of
systematic reviews and better understanding the utilisation of knowledge produced in this
way. The first paper (Henry Potts) reports an ongoing review using a meta-narrative
approach to make sense of the diverse sources of knowledge regarding electronic patient
records. The review method has stressed the importance of understanding knowledge
from within the research tradition in which it was produced; it is argued that this has
important implications for the way that evidence is utilised in the policy making process.
The second paper (Geoff Wong) reflects upon the experience of using an explicit realist
approach in the synthesis of the evidence in Internet based learning. This realist synthesis
offers a method of making sense of the highly heterogeneous and context dependent
evidence which exists in this field thus enabling greater insights into what makes such
educational interventions âworkâ. The third paper (Rod Sheaff) reports a review of the
predominantly qualitative research literature on organisational structures and their
impacts upon policy outcomes in health systems. A scoping study found 14389 relevant
papers of which 1568 were selected for review. These studies were very variable in the
amount and quality of the qualitative data, hence 'evidence', which they reported. The
paper describes an attempt to adapt realist methods so as to synthesise such bodies of
research in ways which take account of this variation in the strength of qualitative
evidence. The fourth paper (Mark Pearson) draws upon the work of Donald Campbell
and colleagues in order to gain a fuller understanding of how systematic reviews are
utilised in the policy making process. It is argued that interpretive approaches to
understanding policy making (such as rhetorical analysis) need to be tempered with a
more nuanced understanding of research validity. The case is made that interpretive
approaches not only can, but should, be melded with research validity to increase
understanding of the policy making process
Analysis of pion elliptic flows and HBT interferometry in a granular quark-gluon plasma droplet model
In many simulations of high-energy heavy-ion collisions on an event-by-event
analysis, it is known that the initial energy density distribution in the
transverse plane is highly fluctuating. Subsequent longitudinal expansion will
lead to many longitudinal tubes of quark-gluon plasma which have tendencies to
break up into many spherical droplets because of sausage instabilities. We are
therefore motivated to use a model of quark-gluon plasma granular droplets that
evolve hydrodynamically to investigate pion elliptic flows and
Hanbury-Brown-Twiss interferometry. We find that the data of pion transverse
momentum spectra, elliptic flows, and HBT radii in \sqrt{s_{NN}}=200 GeV Au +
Au collisions at RHIC can be described well by an expanding source of granular
droplets with an anisotropic velocity distribution.Comment: 9 pages, 6 figures, in Late
Heavy flavor kinetics at the hadronization transition
We investigate the in-medium modification of the charmonium breakup processes
due to the Mott effect for light (pi, rho) and open-charm (D, D*)
quark-antiquark bound states at the chiral/deconfinement phase transition. The
Mott effect for the D-mesons effectively reduces the threshold for charmonium
breakup cross sections, which is suggested as an explanation of the anomalous
J/psi suppression phenomenon in the NA50 experiment. Further implications of
finite-temperature mesonic correlations for the hadronization of heavy flavors
in heavy-ion collisions are discussed.Comment: 4 pages, 2 figures, Contribution to SQM2001 Conference, submitted to
J. Phys.
Electroproduction of the d* dibaryon
The unpolarized cross section for the electroproduction of the isoscalar
di-delta dibaryon is calculated for deuteron target using a
simple picture of elastic electron-baryon scattering from the and the components of the deuteron. The calculated
differential cross section at the electron lab energy of 1 GeV has the value of
about 0.24 (0.05) nb/sr at the lab angle of 10 (30) for the
Bonn B potential when the dibaryon mass is taken to be 2.1 GeV. The cross
section decreases rapidly with increasing dibaryon mass. A large calculated
width of 40 MeV for combined with a small
experimental upper bound of 0.08 MeV for the decay width appears to have
excluded any low-mass model containing a significant admixture of the
configuration.Comment: 11 journal-style pages, 8 figure
Non-equilibrium chemistry and dust formation in AGB stars as probed by SiO line emission
We have performed high spatial resolution observations of SiO line emission
for a sample of 11 AGB stars using the ATCA, VLA and SMA interferometers.
Detailed radiative transfer modelling suggests that there are steep chemical
gradients of SiO in their circumstellar envelopes. The emerging picture is one
where the radial SiO abundance distribution starts at an initial high
abundance, in the case of M-stars consistent with LTE chemistry, that
drastically decreases at a radius of ~1E15 cm. This is consistent with a
scenario where SiO freezes out onto dust grains. The region of the wind with
low abundance is much more extended, typically ~1E16 cm, and limited by
photodissociation. The surpisingly high SiO abundances found in carbon stars
requires non-equilibrium chemical processes.Comment: 2 pages, 1 figure. To be published in the proceedings of the
conference "Why Galaxies Care about AGB Stars", held in Vienna, August 7-11,
2006; F. Kerschbaum, C. Charbonnel, B. Wing eds, ASP Conf.Ser. in pres
Revealing the Archetype: The Journey of a Trecento Madonna and Child at the National Museum of Scotland
The National Museums Scotland Madonna and
Child project sought to uncover and document
the history of a fine polychrome wood carving
attributed to The Master of the Gualino St
Catherine and to prepare it for display. A new
body of knowledge has been assembled by
the interdisciplinary team. The conservation
treatment was informed by this work and led
to further discoveries: the removal of overpaint
exposing a previously hidden underdrawing.
The ethics of the treatment decisions, including
the removal of the Christ Childâs 1960sâ fingers required team dialogue and was opened up for
the public to respond to in a series of blogs.
The discovery of a rich polychromy including
gold and glazed tin has led to further plans to
produce a 3-D colour reconstruction. The collaborations
developed during this project will
facilitate future joint ventures for polychrome
sculpture in Scottish collections
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