6,644 research outputs found
Polling bias and undecided voter allocations: US Presidential elections, 2004 - 2016
Accounting for undecided and uncertain voters is a challenging issue for
predicting election results from public opinion polls. Undecided voters typify
the uncertainty of swing voters in polls but are often ignored or allocated to
each candidate in a simple, deterministic manner. Historically this may have
been adequate because the undecided were comparatively small enough to assume
that they do not affect the relative proportions of the decided voters.
However, in the presence of high numbers of undecided voters, these static
rules may in fact bias election predictions from election poll authors and
meta-poll analysts. In this paper, we examine the effect of undecided voters in
the 2016 US presidential election to the previous three presidential elections.
We show there were a relatively high number of undecided voters over the
campaign and on election day, and that the allocation of undecided voters in
this election was not consistent with two-party proportional (or even)
allocations. We find evidence that static allocation regimes are inadequate for
election prediction models and that probabilistic allocations may be superior.
We also estimate the bias attributable to polling agencies, often referred to
as "house effects".Comment: 32 pages, 9 figures, 6 table
Cosmology with the lights off: Standard sirens in the Einstein Telescope era
We explore the prospects for constraining cosmology using gravitational-wave
(GW) observations of neutron-star binaries by the proposed Einstein Telescope
(ET), exploiting the narrowness of the neutron-star mass function. Double
neutron-star (DNS) binaries are expected to be one of the first sources
detected after "first-light" of Advanced LIGO and are expected to be detected
at a rate of a few tens per year in the advanced era. However the proposed ET
could catalog tens of thousands per year. Combining the measured source
redshift distributions with GW-network distance determinations will permit not
only the precision measurement of background cosmological parameters, but will
provide an insight into the astrophysical properties of these DNS systems. Of
particular interest will be to probe the distribution of delay times between
DNS-binary creation and subsequent merger, as well as the evolution of the
star-formation rate density within ET's detection horizon. Keeping H_0,
\Omega_{m,0} and \Omega_{\Lambda,0} fixed and investigating the precision with
which the dark-energy equation-of-state parameters could be recovered, we found
that with 10^5 detected DNS binaries we could constrain these parameters to an
accuracy similar to forecasted constraints from future CMB+BAO+SNIa
measurements. Furthermore, modeling the merger delay-time distribution as a
power-law, and the star-formation rate (SFR) density as a parametrized version
of the Porciani and Madau SF2 model, we find that the associated astrophysical
parameters are constrained to within ~ 10%. All parameter precisions scaled as
1/sqrt(N), where N is the number of cataloged detections. We also investigated
how precisions varied with the intrinsic underlying properties of the Universe
and with the distance reach of the network (which may be affected by the
low-frequency cutoff of the detector).Comment: 24 pages, 11 figures, 6 tables. Minor changes to reflect published
version. References updated and correcte
Radiative neutron capture on a proton at BBN energies
The total cross section for radiative neutron capture on a proton, , is evaluated at big bang nucleosynthesis (BBN) energies. The
electromagnetic transition amplitudes are calculated up to next-to leading
order within the framework of pionless effective field theory with dibaryon
fields. We also calculate the cross section and the photon
analyzing power for the process from the amplitudes. The
values of low energy constants that appear in the amplitudes are estimated by a
Markov Chain Monte Carlo analysis using the relevant low energy experimental
data. Our result agrees well with those of other theoretical calculations
except for the cross section at some energies estimated by an
R-matrix analysis. We also study the uncertainties in our estimation of the
cross section at relevant BBN energies and find that the
estimated cross section is reliable to within 1% error.Comment: 21 pages and 12 eps figures; 6 eps figures and 2 references added,
and accepted for publication in Phys. Rev.
The Use of Flaps and Grafts in the Treatment of Urethral Stricture Disease
The use of various grafts and flaps plays a critical role in the successful surgical management of urethral stricture disease. A thorough comprehension of relevant anatomy and principles of tissue transfer techniques are essential to understanding the appropriate use of grafts or flaps to optimize outcomes. We briefly review these principles and discuss which technique may be best suited for a given anterior urethral stricture, depending on the location and length of the stricture, the presence or absence of an intact corpus spongiosum, and the availability of adequate and healthy penile skin
Matter formed at the BNL relativistic heavy ion collider
We suggest that the "new form of matter" found just above by RHIC is
made up of tightly bound quark-antiquark pairs, essentially 32 chirally
restored (more precisely, nearly massless) mesons of the quantum numbers of
, , and . Taking the results of lattice gauge
simulations (LGS) for the color Coulomb potential from the work of the
Bielefeld group and feeding this into a relativistic two-body code, after
modifying the heavy-quark lattice results so as to include the
velocity-velocity interaction, all ground-state eigenvalues of the 32 mesons go
to zero at just as they do from below as predicted by the vector
manifestation (VM in short) of hidden local symmetry. This could explain the
rapid rise in entropy up to found in LGS calculations. We argue that how
the dynamics work can be understood from the behavior of the hard and soft
glue.Comment: Final versio
Domains and naïve theories
Human cognition entails domain‐specific cognitive processes that influence memory, attention, categorization, problem‐solving, reasoning, and knowledge organization. This article examines domain‐specific causal theories, which are of particular interest for permitting an examination of how knowledge structures change over time. We first describe the properties of commonsense theories, and how commonsense theories differ from scientific theories, illustrating with children's classification of biological and nonbiological kinds. We next consider the implications of domain‐specificity for broader issues regarding cognitive development and conceptual change. We then examine the extent to which domain‐specific theories interact, and how people reconcile competing causal frameworks. Future directions for research include examining how different content domains interact, the nature of theory change, the role of context (including culture, language, and social interaction) in inducing different frameworks, and the neural bases for domain‐specific reasoning. WIREs Cogni Sci 2011 2 490–502 DOI: 10.1002/wcs.124 For further resources related to this article, please visit the WIREs websitePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87128/1/124_ftp.pd
Western Region Renewable Energy Markets: Implications for the Bureau of Land Management
The purpose of this analysis is to provide the U.S. Department of the Interior (DOI) and the Bureau of Land Management (BLM) with an overview of renewable energy (RE) generation markets, transmission planning efforts, and the ongoing role of the BLM RE projects in the electricity markets of the 11 states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming) that comprise the Western Electricity Coordinating Council (WECC) Region. This analysis focuses on the status of, and projections for, likely development of non-hydroelectric renewable electricity from solar (including photovoltaic [PV] and concentrating solar power [CSP]), wind, biomass and geothermal resources in these states. Absent new policy drivers and without the extension of the DOE loan guarantee program and Treasury's 1603 program, state RPS requirements are likely to remain a primary driver for new RE deployment in the western United States. Assuming no additional policy incentives are implemented, projected RE demand for the WECC states by 2020 is 134,000 GWh. Installed capacity to meet that demand will need to be within the range of 28,000-46,000 MW
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