874 research outputs found
Happiness Research and Cost-Benefit Analysis
A growing body of research on happiness or subjective well-being (SWB) shows, among other things, that people adapt to many injuries more rapidly than is commonly thought, fail to predict the degree of adaptation and hence overestimate the impact of those injuries on their SWB, and, similarly, enjoy small or moderate rather than significant changes in SWB in response to significant changes in income. Some researchers believe that these findings pose a challenge to cost-benefit analysis, and argue that project evaluation decision-procedures based on economic premises should be replaced with procedures that directly maximize subjective well-being. This view turns out to be wrong or, at best, premature. Cost-benefit analysis remains a viable decision-procedure. However, some of the findings in the happiness literature can be used to generate valuations for cost-benefit analysis where current approaches have proven inadequate.
Implementing Cost-Benefit Analysis When Preferences Are Distorted
Cost-benefit analysis is routinely used by government agencies in order to evaluate projects, but it remains controversial among academics. This paper argues that cost-benefit analysis is best understood as a welfarist decision procedure and that use of cost-benefit analysis is more likely to maximize overall well-being than is use of alternative decision-procedures. The paper focuses on the problem of distorted preference. A person\u27s preferences are distorted when his or her satisfaction does not enhance that person\u27s well-being. Preferences typically thought to be distorted in this sense include disinterested preferences, uninformed preferences, adaptive preferences, and objectively bad preferences; further, preferences may be a poor guide to maximizing aggregate well-being when wealth is unequally distributed. We argue that government agencies currently recognize these problems but respond to them in an ad hoc way, and that a more systematic treatment of these problems is warranted. The paper describes conditions under which agencies should correct for distorted preferences, for example, by constructing informed or non-adaptive preferences, discounting objectively bad preferences, and treating people differentially on the basis of wealth
Managing Interspecies Competition to Improve Spring Pasture
Orchardgrass (Dactylis glomerata L.) is one of the earliest maturing pasture grasses utilized in the northeastern United States. However, wet springs can delay forage harvesting resulting in advanced forage maturity and reduction in nutritive value. Chicory (Cichorium intybus L.) is a tall, upright-growing forb that shows promise as a high-energy companion crop to orchardgrass and may delay orchardgrass maturity through shading effects on plant morphology. The objective of this study was to evaluate monocultures and mixtures of orchardgrass, chicory, and white clover (Trifolium repens L.) over two consecutive springs to determine the effects of species diversity on plant maturity, nutritive characteristics, and botanical composition of forage mass. Forage monocultures and mixtures were planted in central Pennsylvania in August 2018 and were observed for two years with three harvests occurring each year (one each in spring, summer, and fall). In the first spring, orchardgrass demonstrated nine days delay in maturity when grown with chicory as compared to when grown in monocultures or in orchardgrass-white clover mixtures. Although orchardgrass was at an earlier developmental stage, fiber concentrations were similar when grown with or without chicory. Additionally, in the first spring, orchardgrass mixtures containing chicory had 1.5x greater forage mass than orchardgrass monocultures and orchardgrass-white clover mixtures. Chicory biomass was low in the second spring, likely due to winterkill following a late fall harvest the previous year, resulting in a negligible effect on orchardgrass. However, orchardgrass-chicory-white clover mixtures (even with low amounts of chicory in the second year) had the greatest forage mass and nutritive value yield over both years, indicating that these mixtures can provide greater agronomic benefits than orchardgrass monocultures
From Current to Constituent Quarks: a Renormalization Group Improved Hamiltonian-based Description of Hadrons
A model which combines the perturbative behavior of QCD with low energy
phenomenology in a unified framework is developed. This is achieved by applying
a similarity transformation to the QCD Hamiltonian which removes interactions
between the ultraviolet cutoff and an arbitrary lower scale. Iteration then
yields a renormalization group improved effective Hamiltonian at the hadronic
energy scale. The procedure preserves the standard ultraviolet behavior of QCD.
Furthermore, the Hamiltonian evolves smoothly to a phenomenological low energy
behavior below the hadronic scale. This method has the benefit of allowing
radiative corrections to be directly incorporated into nonperturbative
many-body techniques. It is applied to Coulomb gauge QCD supplemented with a
low energy linear confinement interaction. A nontrivial vacuum is included in
the analysis via a Bogoliubov-Valatin transformation. Finally, the formalism is
applied to the vacuum gap equation, the quark condensate, and the dynamical
quark mass.Comment: 36 pages, RevTeX, 5 ps figures include
A Developmental Examination of Amygdala Response to Facial Expressions
Several lines of evidence implicate the amygdala in face-emotion processing, particularly for fearful facial expressions. Related findings suggest that face-emotion processing engages the amygdala within an interconnected circuitry that can be studied using a functional-connectivity approach. Past work also underscores important functional changes in the amygdala during development. Taken together, prior research on amygdala function and development reveals a need for more work examining developmental changes in the amygdalaâs response to fearful faces and in amygdala functional connectivity during face processing. The present study used event-related functional magnetic resonance imaging to compare 31 adolescents (9â17 years old) and 30 adults (21â40 years old) on activation to fearful faces in the amygdala and other regions implicated in face processing. Moreover, these data were used to compare patterns of amygdala functional connectivity in adolescents and adults. During passive viewing, adolescents demonstrated greater amygdala and fusiform activation to fearful faces than did adults. Functional connectivity analysis revealed stronger connectivity between the amygdala and the hippocampus in adults than in adolescents. Within each group, variability in age did not correlate with amygdala response, and sex-related developmental differences in amygdala response were not found. Eye movement data collected outside of the magnetic resonance imaging scanner using the same task suggested that developmental differences in amygdala activation were not attributable to differences in eye-gaze patterns. Amygdala hyperactivation in response to fearful faces may explain increased vulnerability to affective disorders in adolescence; stronger amygdalaâhippocampus connectivity in adults than adolescents may reflect maturation in learning or habituation to facial expressions
Chiral Extrapolation, Renormalization, and the Viability of the Quark Model
The relationship of the quark model to the known chiral properties of QCD is
a longstanding problem in the interpretation of low energy QCD. In particular,
how can the pion be viewed as both a collective Goldstone boson quasiparticle
and as a valence quark antiquark bound state where universal hyperfine
interactions govern spin splittings in the same way as in the heavy quark
systems. We address this issue in a simplified model which; however, reproduces
all features of QCD relevant to this problem. A comparison of the many-body
solution to our model and the constituent quark model demonstrates that the
quark model is sufficiently flexible to describe meson hyperfine splitting
provided proper renormalization conditions and correct degrees of freedom are
employed consistently.Comment: 6 pages, 2 eps figures, uses revtex. Version to appear in Phys. Rev.
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Hybrid Meson Decay Phenomenology
The phenomenology of a newly developed model of hybrid meson decay is
developed. The decay mechanism is based on the heavy quark expansion of QCD and
the strong coupling flux tube picture of nonperturbative glue. A comprehensive
list of partial decay widths of a wide variety of light, , ,
and hybrid mesons is presented. Results which appear approximately
universal are highlighted along with those which distinguish different hybrid
decay models. Finally, we examine several interesting hybrid candidates in
detail.Comment: 37 pages, 2 figures, 6 tables, Revte
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