2,293 research outputs found
Regret Aversion and False Reference Points in Residential Real Estate
This study empirically exams the combination of regret aversion and false reference points in a residential real estate context. Survey respondents were put in a hypothetical situation, where they had purchased an investment property several years ago. Hindsight knowledge about a foregone all time high was introduced. As hypothesized, respondents on average expressed higher regret if they had actively failed to sell at the all time high (commission scenario) than if they had simply been unaware of the potential gain (omission scenario). Women were found to be more susceptible to regret aversion and false reference points than men.
Dynamically-Coupled Oscillators -- Cooperative Behavior via Dynamical Interaction --
We propose a theoretical framework to study the cooperative behavior of
dynamically coupled oscillators (DCOs) that possess dynamical interactions.
Then, to understand synchronization phenomena in networks of interneurons which
possess inhibitory interactions, we propose a DCO model with dynamics of
interactions that tend to cause 180-degree phase lags. Employing an approach
developed here, we demonstrate that although our model displays synchronization
at high frequencies, it does not exhibit synchronization at low frequencies
because this dynamical interaction does not cause a phase lag sufficiently
large to cancel the effect of the inhibition. We interpret the disappearance of
synchronization in our model with decreasing frequency as describing the
breakdown of synchronization in the interneuron network of the CA1 area below
the critical frequency of 20 Hz.Comment: 10 pages, 3 figure
First Keck Nulling Observations of a Young Stellar Object: Probing the Circumstellar Environment of the Herbig Ae star MWC 325
We present the first N-band nulling plus K- and L-band V2 observations of a
young stellar object, MWC325, taken with the 85 m baseline Keck Interferometer.
The Keck nuller was designed for the study of faint dust signatures associated
with debris disks, but it also has a unique capability for studying the
temperature and density distribution of denser disks found around young stellar
objects. Interferometric observations of MWC 325 at K, L and N encompass a
factor of five in spectral range and thus, especially when spectrally dispersed
within each band, enable characterization of the structure of the inner disk
regions where planets form. Fitting our observations with geometric models such
as a uniform disk or a Gaussian disk show that the apparent size increases
monotonically with wavelength in the 2-12 um wavelength region, confirming the
widely held assumption based on radiative transfer models, now with spatially
resolved measurements over broad wavelength range, that disks are extended with
a temperature gradient. The effective size is a factor of about 1.3 and 2
larger in the L-band and N-band, respectively, compared to that in the K-band.
The existing interferometric measurements and the spectral energy distribution
can be reproduced by a flat disk or a weakly-shadowed nearly flat-disk model,
with only slight flaring in the outer regions of the disk, consisting of
representative "sub-micron" (0.1 um) and "micron" (2 um) grains of a 50:50
ratio of silicate and graphite. This is marked contrast with the disks
previously found in other Herbig Ae/Be stars suggesting a wide variety in the
disk properties among Herbig Ae/Be stars.Comment: Accepted for publication in the Ap
The prevalence of visual anomalies among adult offenders
Fifty-three incarcerated adult sexual offenders from a voluntary treatment program at the Oregon State Correctional Facility were screened for visual anomalies. Subjects were divided into two groups based on intellectual function, one a higher functioning (HF) group, and one a social skills (SS) group. The two groups were compared based on a screening battery probing ocular health, eye movement skills, visual perceptual abilities and accommodative/vergence abilities. The ocular health did not differ between the two groups or from the general population. Differences were found in visual perceptual function between the high and low functioning groups. The HF group outperformed the lower on all perceptual and eye movement tests except the subjective eye movement evaluation. Unexpected differences were found between the two groups in the areas of accommodative posture, vergence facility, and distance monocular acuities
Exploring the Relationships between South Texas Northern Bobwhite Populations and Cecal Worms via System Dynamics
Community ecology historically focused on plants and free-living organisms; however, problems such as defining habitat boundaries and obtaining adequate sample sizes arise when evaluating such communities. The unique nature of host-helminth systems allows parasite community ecologists to avoid these problems when testing ecological hypotheses. Unlike free-living communities that have artificially constructed boundaries, parasite communities have well-defined unambiguous boundaries within host individuals. Due to the inherently complex and dynamic nature of ecological systems, traditional experimental methods often require expensive, long-term trials beyond investigatorsā time and resource budgets. Conversely, a system dynamics approach facilitates learning about such systems via simulation of ecosystem processes integrated with historical data (both quantitative and qualitative). Relatively few studies focus on parasites in South Texas, USA, although research on avian host-parasite systems has shown that parasites can potentially regulate host populations. The northern bobwhite (Colinus virginianus; hereafter, bobwhite) is a game species of ecological, economic, cultural, and recreational importance in Texas that has been experiencing a long-term, widespread decline. To holistically examine the bobwhite-helminth system in South Texas, we created a system dynamics model capturing the feedback relationships between a South Texas bobwhite population, a grasshopper (family Acrididae) population, and the corresponding cecal worm (Aulonocephalus pennula) populations on a hypothetical 1,000-acre ranch in South Texas. The model structure, constructed in VensimĀ® PLE 7.2 software (Ventana Systems, Inc.), integrates the hypothesized biotic and abiotic drivers (precipitation, parasite load, insect abundance, and quail density) unique to the host-helminth system over 7 years (2012ā2019). Our specific objectives were to 1) develop a working baseline model to replicate the synergistic population dynamics among bobwhite, grasshopper, and cecal worm populations and then 2) test hypotheses about each populationās boom-and-bust cycles resulting from environmental stressors (e.g., drought). Applications of the model can provide landowners and natural resource managers with a better understanding of the complex dynamics occurring among bobwhite, grasshopper, and cecal worm populations in South Texas
Strengthening Synergies: How Action to Achieve Post-2020 Global Biodiversity Conservation Targets Can Contribute to Mitigating Climate Change
The essential contribution of nature to addressing climate change provides an opportunity to strengthen the links between the United Nations Framework Convention on Climate Change and the Convention on Biological Diversity. As we move towards the next Conferences of the Parties of both Conventions, there is a need to assess explicitly the role of nature in helping to meet the goals of these agreements efficiently and effectively. This series of reports aims to shed light on this topic by assessing the potential contribution that achieving biodiversity conservation targets can make to climate change mitigation. By doing so, it aims to provide both context and mandate for discussions under both Conventions on the role of nature-based solutions in climate change mitigation and links to biodiversity conservation action
Neuron splitting in compute-bound parallel network simulations enables runtime scaling with twice as many processors
Neuron tree topology equations can be split into two subtrees and solved on different processors with no change in accuracy, stability, or computational effort; communication costs involve only sending and receiving two double precision values by each subtree at each time step. Splitting cells is useful in attaining load balance in neural network simulations, especially when there is a wide range of cell sizes and the number of cells is about the same as the number of processors. For compute-bound simulations load balance results in almost ideal runtime scaling. Application of the cell splitting method to two published network models exhibits good runtime scaling on twice as many processors as could be effectively used with whole-cell balancing
First L-band Interferometric Observations of a Young Stellar Object: Probing the Circumstellar Environment of MWC 419
We present spatially-resolved K- and L-band spectra (at spectral resolution R
= 230 and R = 60, respectively) of MWC 419, a Herbig Ae/Be star. The data were
obtained simultaneously with a new configuration of the 85-m baseline Keck
Interferometer. Our observations are sensitive to the radial distribution of
temperature in the inner region of the disk of MWC 419. We fit the visibility
data with both simple geometric and more physical disk models. The geometric
models (uniform disk and Gaussian) show that the apparent size increases
linearly with wavelength in the 2-4 microns wavelength region, suggesting that
the disk is extended with a temperature gradient. A model having a power-law
temperature gradient with radius simultaneously fits our interferometric
measurements and the spectral energy distribution data from the literature. The
slope of the power-law is close to that expected from an optically thick disk.
Our spectrally dispersed interferometric measurements include the Br gamma
emission line. The measured disk size at and around Br gamma suggests that
emitting hydrogen gas is located inside (or within the inner regions) of the
dust disk.Comment: Accepted for publication in Ap
Quantum algorithm and circuit design solving the Poisson equation
The Poisson equation occurs in many areas of science and engineering. Here we
focus on its numerical solution for an equation in d dimensions. In particular
we present a quantum algorithm and a scalable quantum circuit design which
approximates the solution of the Poisson equation on a grid with error
\varepsilon. We assume we are given a supersposition of function evaluations of
the right hand side of the Poisson equation. The algorithm produces a quantum
state encoding the solution. The number of quantum operations and the number of
qubits used by the circuit is almost linear in d and polylog in
\varepsilon^{-1}. We present quantum circuit modules together with performance
guarantees which can be also used for other problems.Comment: 30 pages, 9 figures. This is the revised version for publication in
New Journal of Physic
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