1,318 research outputs found
Fairness Beyond Disparate Treatment & Disparate Impact: Learning Classification without Disparate Mistreatment
Automated data-driven decision making systems are increasingly being used to
assist, or even replace humans in many settings. These systems function by
learning from historical decisions, often taken by humans. In order to maximize
the utility of these systems (or, classifiers), their training involves
minimizing the errors (or, misclassifications) over the given historical data.
However, it is quite possible that the optimally trained classifier makes
decisions for people belonging to different social groups with different
misclassification rates (e.g., misclassification rates for females are higher
than for males), thereby placing these groups at an unfair disadvantage. To
account for and avoid such unfairness, in this paper, we introduce a new notion
of unfairness, disparate mistreatment, which is defined in terms of
misclassification rates. We then propose intuitive measures of disparate
mistreatment for decision boundary-based classifiers, which can be easily
incorporated into their formulation as convex-concave constraints. Experiments
on synthetic as well as real world datasets show that our methodology is
effective at avoiding disparate mistreatment, often at a small cost in terms of
accuracy.Comment: To appear in Proceedings of the 26th International World Wide Web
Conference (WWW), 2017. Code available at:
https://github.com/mbilalzafar/fair-classificatio
HST Observations of the Host Galaxies of BL Lacertae Objects
Six BL Lac objects from the complete 1 Jy radio-selected sample of 34 objects
were observed in Cycle 5 with the HST WFPC2 camera to an equivalent limiting
flux of mu_I~26 mag/arcsec^2. Here we report results for the second half of
this sample, as well as new results for the first three objects, discussed
previously by Falomo et al. (1997). In addition, we have analyzed in the same
way HST images of three X-ray-selected BL Lacs observed by Jannuzi et al.
(1997). The ensemble of 9 BL Lac objects spans the redshift range from z=0.19
to ~1. Host galaxies are clearly detected in seven cases, while the other two,
at z~0.258 (redshift highly uncertain) and z=0.997, are not resolved. The HST
images constitute a homogeneous data set with unprecedented morphological
information between a few tenths of an arcsecond and several arcseconds from
the nucleus, allowing us in 6 of the 7 detected host galaxies to rule out
definitively a pure disk light profile. The host galaxies are luminous
ellipticals with an average absolute magnitude of M_I~-24.6 mag (with
dispersion 0.7 mag), more than a magnitude brighter than L* and comparable to
brightest cluster galaxies. The morphologies are generally smooth and have
small ellipticities (epsilon<0.2). Given such roundness, there is no obvious
alignment with the more linear radio structures. In the six cases for which we
have HST WFPC2 images in two filters, the derived color profiles show no strong
spatial gradients and are as expected for K-corrected passively evolving
elliptical galaxies. The host galaxies of the radio-selected and X-ray-selected
BL Lacs for this very limited sample are comparable in both morphology and
luminosity.Comment: 23 pages, including 6 postscript figures and 3 tables (embedded).
Latex requires aaspp4.sty and psfig.sty (not included). Accepted for
publication in the Astrophysical Journa
Comparing ultra-high spatial resolution remote-sensing methods in mapping peatland vegetation
Peer reviewe
Stigma and Social Power: Expecting to Interact with an Obese Person Activates Power in the Self-concept
People's sense of power is often a more crucial determinant of their behavior than their actual level of power. In this paper, we suggest that individuals may perceive themselves as more powerful when anticipating interaction with a member of a stigmatized out-group than with a member of a nonstigmatized group. Normal weight participants (N = 77) expected to have an interaction with a target randomly identified as obese or thin. Participants were quicker to endorse words describing themselves in terms of traits associated with power when the target was obese than thin. They were also likely to expect greater interpersonal power, to endorse more negative attitudes towards obese people and to form more negative impressions, if the target was obese rather than thin. These findings suggest that a perception of empowerment is spontaneously activated prior to interaction with an obese person.http://www.informaworld.com/smpp/content~db=all~content=a907123882~frm=titlelinkSCOPUS: ar.jinfo:eu-repo/semantics/publishe
Numerical schemes for a model for nonlinear dispersive waves
A description is given of a number of numerical schemes to solve an evolution equation that arises when modelling the propagation of water waves in a channel. The discussion also includes the results of numerical experiments made with each of the schemes. It is suggested, on the basis of these experiments, that one of the schemes may have (discrete) solitary-wave solutions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25569/1/0000111.pd
ENHANCED GROWTH RATE AND SILANE UTILIZATION IN AMORPHOUS SILICON AND NANOCRYSTALLINE-SILICON SOLAR CELL DEPOSITION VIA GAS PHASE ADDITIVES
Air Products set out to investigate the impact of additives on the deposition rate of both ÃÂõCSi and ÃÂñSi-H films. One criterion for additives was that they could be used in conventional PECVD processing, which would require sufficient vapor pressure to deliver material to the process chamber at the required flow rates. The flow rate required would depend on the size of the substrate onto which silicon films were being deposited, potentially ranging from 200 mm diameter wafers to the 5.7 m2 glass substrates used in GEN 8.5 flat-panel display tools. In choosing higher-order silanes, both disilane and trisilane had sufficient vapor pressure to withdraw gas at the required flow rates of up to 120 sccm. This report presents results obtained from testing at Air ProductsâÃÂàelectronic technology laboratories, located in Allentown, PA, which focused on developing processes on a commercial IC reactor using silane and mixtures of silane plus additives. These processes were deployed to compare deposition rates and film properties with and without additives, with a goal of maximizing the deposition rate while maintaining or improving film properties
Examining the role of menthol cigarettes in progression to established T smoking among youth
Background: Menthol, a flavoring compound added to cigarettes, makes cigarettes more appealing to youth and inexperienced smokers and increases cigarettes\u27 abuse liability. However, limited studies are available on menthol\u27s role in smoking progression.
Methods: To assess the association between menthol in cigarettes and progression to established smoking, we used five waves of data from the Evaluation of Public Education Campaign on Teen Tobacco Cohort Study, a nationally representative longitudinal survey of U.S. youth conducted as part of “The Real Cost” evaluation. We used discrete time survival analysis to model the occurrence of two event outcomes—progression to established, current smoking and progression to established, frequent smoking—using a logit model with a menthol use indicator as the key explanatory variable. Based on this framework, we estimated the effect of prior menthol use on the odds of smoking progression.
Results: In the progression to established, current smoking model, prior menthol use was significantly associated with progression [adjusted odds ratio (aOR) = 1.80, p \u3c .05, confidence interval (CI) = (1.03–3.16)]. While results were in a similar direction for the model of progression to established, frequent smoking, the association between prior menthol use and this progression model did not reach significance [aOR=1.56, CI = (0.80–3.03)].
Conclusion: The results suggest a relationship between using menthol cigarettes and progression from experi- mental to established, current smoking among youth. This study adds to a growing literature base that supports that menthol cigarettes, compared to nonmenthol cigarettes, put youth at increased risk for regular cigarette use
Segregate or cooperate- a study of the interaction between two species of Dictyostelium
<p>Abstract</p> <p>Background</p> <p>A major challenge for evolutionary biology is explaining altruism, particularly when it involves death of one party and occurs across species. Chimeric fruiting bodies of <it>Dictyostelium discoideum </it>and <it>Dictyostelium purpureum </it>develop from formerly independent amoebae, and some die to help others. Here we examine co-aggregation between <it>D. discoideum </it>and <it>D. purpureum</it>, determine its frequency and which party benefits, and the extent of fair play in contribution to the altruistic caste.</p> <p>Results</p> <p>We mixed cells from both species in equal proportions, and then we analyzed 198 individual fruiting bodies, which always had either a <it>D. discoideum </it>or <it>D. purpureum </it>phenotype (<it>D. discoideum</it>- 98, <it>D. purpureum</it>- 100). Fifty percent of the fruiting bodies that looked like <it>D. discoideum </it>and 22% of the fruiting bodies that looked like <it>D. purpureum </it>were chimeric, though the majority of spores in any given fruiting body belonged to one species (<it>D. discoideum </it>fruiting bodies- 0.85 ± 0.03, <it>D. purpureum </it>fruiting bodies- 0.94 ± 0.02). Clearly, there is species level recognition occurring that keeps the cells mostly separate. The number of fruiting bodies produced with the <it>D. discoideum </it>phenotype increased from 225 ± 32 fruiting bodies when <it>D. discoideum </it>was alone to 486 ± 61 in the mix treatments. However, the number of <it>D. discoideum </it>spores decreased, although not significantly, from 2.75e<sup>7 </sup>± 1.29e<sup>7 </sup>spores in the controls to 2.06e<sup>7 </sup>± 8.33e<sup>6 </sup>spores in the mix treatments. <it>D. purpureum </it>fruiting body and spore production decreased from 719 ± 111 fruiting bodies and 5.81e<sup>7 </sup>± 1.26e<sup>7 </sup>spores in the controls to 394 ± 111 fruiting bodies and 9.75e<sup>6 </sup>± 2.25e<sup>6 </sup>spores in the mix treatments.</p> <p>Conclusion</p> <p>Both species appear to favor clonality but can cooperate with each other to produce fruiting bodies. Cooperating amoebae are able to make larger fruiting bodies, which are advantageous for migration and dispersal, but both species here suffer a cost in producing fewer spores per fruiting body.</p
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