7,497 research outputs found
Envy Freeness in Experimental Fair Division Problems
In the recent experimental literature several social preference models have been suggested that address observed behavior not reducible to the pursuit of self-interest. Inequality aversion is one such model where preferences are distributional. Frequently, envy is suggested as the underlying rationale for inequality aversion. Envy is a central criterion in the theoretical literature on fair division, whose definition (Foley 1967) differs from the more casual use of the word in the experimental literature. We present and discuss results from free-form bargaining experiments on fair division problems where the role of envy in Foley’s sense can be analyzed and compared to social preferences. We find that envy freeness does matter as a secondary criterion.Fairness, Envy Freeness, Social Preferences, Bargaining
The Magnetic Field of L1544: I. Near-Infrared Polarimetry and the Non-Uniform Envelope
The magnetic field (B-field) of the starless dark cloud L1544 has been
studied using near-infrared (NIR) background starlight polarimetry (BSP) and
archival data in order to characterize the properties of the plane-of-sky
B-field. NIR linear polarization measurements of over 1,700 stars were obtained
in the H-band and 201 of these were also measured in the K-band. The NIR BSP
properties are correlated with reddening, as traced using the RJCE (H-M)
method, and with thermal dust emission from the L1544 cloud and envelope seen
in Herschel maps. The NIR polarization position angles change at the location
of the cloud and exhibit their lowest dispersion of position angles there,
offering strong evidence that NIR polarization traces the plane-of-sky B-field
of L1544. In this paper, the uniformity of the plane-of-sky B-field in the
envelope region of L1544 is quantitatively assessed. This allowed evaluating
the approach of assuming uniform field geometry when measuring relative
mass-to-flux ratios in the cloud envelope and core based on averaging of the
envelope radio Zeeman observations, as in Crutcher et al. (2009). In L1544, the
NIR BSP shows the envelope B-field to be significantly non-uniform and likely
not suitable for averaging Zeeman properties without treating intrinsic
variations. Deeper analyses of the NIR BSP and related data sets, including
estimates of the B-field strength and testing how it varies with position and
gas density, are the subjects of later papers in this series.Comment: 16 pages, 9 figures; accepted for publication in The Astrophysical
Journa
Josephson Coupling in the Dissipative State of a Thermally Hysteretic -SQUID
Micron-sized superconducting interference devices (-SQUIDs) based on
constrictions optimized for minimizing thermal runaway are shown to exhibit
voltage oscillations with applied magnetic flux despite their hysteretic
behavior. We explain this remarkable feature by a significant supercurrent
contribution surviving deep into the resistive state, due to efficient heat
evacuation. A resistively shunted junction model, complemented by a thermal
balance determining the amplitude of the critical current, describes well all
experimental observations, including the flux modulation of the (dynamic)
retrapping current and voltage by introducing a single dimensionless parameter.
Thus hysteretic -SQUIDs can be operated in the voltage read-out mode with
a faster response. The quantitative modeling of this regime incorporating both
heating and phase dynamics paves the way for further optimization of
-SQUIDs for nano-magnetism.Comment: 10 pages, 11 figures, Revise
The unusual distribution of molecular gas and star formation in Arp 140
We investigate the atomic and molecular interstellar medium and star
formation of NGC 275, the late-type spiral galaxy in Arp 140, which is
interacting with NGC 274, an early-type system. The atomic gas (HI)
observations reveal a tidal tail from NGC 275 which extends many optical radii
beyond the interacting pair. The HI morphology implies a prograde encounter
between the galaxy pair approximately 1.5 x 10**8 years ago. The Halpha
emission from NGC 275 indicates clumpy irregular star-formation, clumpiness
which is mirrored by the underlying mass distribution as traced by the Ks-band
emission. The molecular gas distribution is striking in its anti-correlation
with the {HII regions. Despite the evolved nature of NGC 275's interaction and
its barred potential, neither the molecular gas nor the star formation are
centrally concentrated. We suggest that this structure results from stochastic
star formation leading to preferential consumption of the gas in certain
regions of the galaxy. In contrast to the often assumed picture of interacting
galaxies, NGC 275, which appears to be close to merger, does not display
enhanced or centrally concentrated star formation. If the eventual merger is to
lead to a significant burst of star formation it must be preceded by a
significant conversion of atomic to molecular gas as at the current rate of
star formation all the molecular gas will be exhausted by the time the merger
is complete.Comment: 13 paper, accepted my Monthly Notices of the Royal Astronomical
Societ
Antihyperglycemic Medications and Hypoglycemia in Older Adults with Diabetes
Background: In the last decade, several new antihyperglycemic medications have been approved to treat people with diabetes. However, the hypoglycemia risk of these medications in older adults in routine clinical practice remains unclear. Further, there is limited understanding as to how these medications are being prescribed to older adults in our region.
Methods: We carried out retrospective, population-based studies of adults age 66 and older in Ontario, Canada using linked healthcare databases. We first investigated the real-world hypoglycemia risk of 2 antihyperglycemic medications – glyburide and modified-release gliclazide. In an ecological study, we then examined trends in antihyperglycemic medication prescriptions, and in this setting, investigated hospital encounters for hypoglycemia.
Results: Initiating glyburide vs gliclazide as monotherapy or in the presence of metformin was associated with a significantly higher risk of a hospital encounter with hypoglycemia. Over the last decade, newer and safer antihyperglycemic medications have been prescribed to older adults in our region. In this setting, the overall percentage of patients with a hospital encounter with hypoglycemia has declined.
Conclusions: Antihyperglycemic medications differ in their real-world hypoglycemia risk in older patients. In the setting of newer and safer antihyperglycemic medications, encounters for hypoglycemia have declined
Inequality Aversion and Efficiency with Ordinal and Cardinal Social Preferences – An Experimental Study
In this paper, we report on a series of free-form bargaining experiments inwhich two players have to distribute four indivisible goods among themselves. In one treatment, players are informed about the monetary payoffs associated with each bundle of goods; in a second treatment only the ordinal ranking of the bundles is given. We find that in both cases, inequality aversion plays a prominent role. In the ordinal treatment, individuals apparently use the ranks in the respective preference orderings over bundles of goods as a substitute for the unknown monetary value. Allocations that distribute the value (money or ranks, respectively) most equally serve as natural “reference points” forthe bargaining processes. Frequently, such “equal split” allocations are chosen by our subjects even though they are Pareto dominated; but also if they are rejected for that reason they matter in a specific way: whether a Pareto optimal allocation is chosen or not depends on whether or not it is a Pareto improvement relative to the equal split. Interestingly, we find much less Pareto-damaging behavior due to inequality aversion in the ordinal treatment
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