953 research outputs found
Keeping the collectivity in mind?
The key question in this three way debate is the role of the collectivity and of agency. Collins and Shrager debate whether cognitive psychology has, like the sociology of knowledge, always taken the mind to extend beyond the individual. They agree that irrespective of the history, socialization is key to understanding the mind and that this is compatible with Clark’s position; the novelty in Clark’s “extended mind” position appears to be the role of the material rather than the role of other minds. Collins and Clark debate the relationship between self, agency, and the human collectivity. Collins argues that the Clark’s extended mind fails to stress the asymmetry of the relationship between the self and its material “scaffolding.” Clark accepts that there is asymmetry but that an asymmetrical ensemble is sufficient to explain the self. Collins says that we know too little about the material world to pursue such a model to the exclusion of other approaches including that both the collectivity and language have agency. The collectivity must be kept in mind! (Though what follows is a robust exchange of views it is also a cooperative effort, authors communicating “backstage” with each other to try to make the disagreements as clear and to the point as possible.
Problem Formulation and Fairness
Formulating data science problems is an uncertain and difficult process. It
requires various forms of discretionary work to translate high-level objectives
or strategic goals into tractable problems, necessitating, among other things,
the identification of appropriate target variables and proxies. While these
choices are rarely self-evident, normative assessments of data science projects
often take them for granted, even though different translations can raise
profoundly different ethical concerns. Whether we consider a data science
project fair often has as much to do with the formulation of the problem as any
property of the resulting model. Building on six months of ethnographic
fieldwork with a corporate data science team---and channeling ideas from
sociology and history of science, critical data studies, and early writing on
knowledge discovery in databases---we describe the complex set of actors and
activities involved in problem formulation. Our research demonstrates that the
specification and operationalization of the problem are always negotiated and
elastic, and rarely worked out with explicit normative considerations in mind.
In so doing, we show that careful accounts of everyday data science work can
help us better understand how and why data science problems are posed in
certain ways---and why specific formulations prevail in practice, even in the
face of what might seem like normatively preferable alternatives. We conclude
by discussing the implications of our findings, arguing that effective
normative interventions will require attending to the practical work of problem
formulation.Comment: Conference on Fairness, Accountability, and Transparency (FAT* '19),
January 29-31, 2019, Atlanta, GA, US
Measuring Parton Densities in the Pomeron
We present a program to measure the parton densities in the pomeron using
diffractive deep inelastic scattering and diffractive photoproduction, and to
test the resulting parton densities by applying them to other processes such as
the diffractive production of jets in hadron-hadron collisions. Since QCD
factorization has been predicted NOT to apply to hard diffractive scattering,
this program of fitting and using parton densities might be expected to fail.
Its success or failure will provide useful information on the space-time
structure of the pomeron.Comment: Contains revisions based on Phys. Rev. D referee comments. RevTeX
version 3, epsf, 31 pages. Uuencoded compressed postscript figures appended.
Uncompressed postscript files available at
ftp://ftp.phys.psu.edu/pub/preprint/psuth136
Emission Line Galaxies in the STIS Parallel Survey I: Observations and Data Analysis
In the first three years of operation STIS obtained slitless spectra of
approximately 2500 fields in parallel to prime HST observations as part of the
STIS Parallel Survey (SPS). The archive contains almost 300 fields at high
galactic latitude (|b|>30) with spectroscopic exposure times greater than 3000
seconds. This sample contains 220 fields (excluding special regions and
requiring a consistent grating angle) observed between 6 June 1997 and 21
September 2000, with a total survey area of about 160 square arcminutes. At
this depth, the SPS detects an average of one emission line galaxy per three
fields. We present the analysis of these data, and the identification of 131
low to intermediate redshift galaxies detected by optical emission lines. The
sample contains 78 objects with emission lines that we infer to be redshifted
[OII]3727 emission at 0.43<z<1.7. The comoving number density of these objects
is comparable to that of H-alpha emitting galaxies in the NICMOS parallel
observations. One quasar and three probable Seyfert galaxies are detected. Many
of the emission-line objects show morphologies suggestive of mergers or
interactions. The reduced data are available upon request from the authors.Comment: 58 preprint pages, including 26 figures; accepted for publication in
ApJ
Scaling of the B and D meson spectrum in lattice QCD
We give results for the and the meson spectrum using NRQCD on the
lattice in the quenched approximation. The masses of radially and orbitally
excited states are calculated as well as -wave hyperfine and -wave fine
structure. Radially excited -states are observed for the first time. Radial
and orbital excitation energies match well to experiment, as does the
strange-non-strange -wave splitting. We compare the light and heavy quark
mass dependence of various splittings to experiment. Our -results cover a
range in lattice spacings of more than a factor of two. Our -results are
from a single lattice spacing and we compare them to numbers in the literature
from finer lattices using other methods. We see no significant dependence of
physical results on the lattice spacing.
PACS: 11.15.Ha 12.38.Gc 14.40.Lb 14.40.NdComment: 78 pages, 29 tables, 30 figures Revised version. Minor corrections to
spelling and wordin
A Pair of Compact Red Galaxies at Redshift 2.38, Immersed in a 100 kpc Scale Ly-alpha Nebula
We present Hubble Space Telescope (HST) and ground-based observations of a
pair of galaxies at redshift 2.38, which are collectively known as 2142-4420 B1
(Francis et al. 1996). The two galaxies are both luminous extremely red objects
(EROs), separated by 0.8 arcsec. They are embedded within a 100 kpc scale
diffuse Ly-alpha nebula (or blob) of luminosity ~10^44 erg/s.
The radial profiles and colors of both red objects are most naturally
explained if they are young elliptical galaxies: the most distant yet found. It
is not, however, possible to rule out a model in which they are abnormally
compact, extremely dusty starbursting disk galaxies. If they are elliptical
galaxies, their stellar populations have inferred masses of ~10^11 solar masses
and ages of ~7x10^8 years. Both galaxies have color gradients: their centers
are significantly bluer than their outer regions. The surface brightness of
both galaxies is roughly an order of magnitude greater than would be predicted
by the Kormendy relation. A chain of diffuse star formation extending 1 arcsec
from the galaxies may be evidence that they are interacting or merging.
The Ly-alpha nebula surrounding the galaxies shows apparent velocity
substructure of amplitude ~ 700 km/s. We propose that the Ly-alpha emission
from this nebula may be produced by fast shocks, powered either by a galactic
superwind or by the release of gravitational potential energy.Comment: 33 pages, 9 figures, ApJ in press (to appear in Jun 10 issue
Institutional Experience with Voriconazole Compared with Liposomal Amphotericin B as Empiric Therapy for Febrile Neutropenia
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90034/1/phco.27.7.970.pd
Spatio-temporal evolution of global surface temperature distributions
Climate is known for being characterised by strong non-linearity and chaotic
behaviour. Nevertheless, few studies in climate science adopt statistical
methods specifically designed for non-stationary or non-linear systems. Here we
show how the use of statistical methods from Information Theory can describe
the non-stationary behaviour of climate fields, unveiling spatial and temporal
patterns that may otherwise be difficult to recognize. We study the maximum
temperature at two meters above ground using the NCEP CDAS1 daily reanalysis
data, with a spatial resolution of 2.5 by 2.5 degree and covering the time
period from 1 January 1948 to 30 November 2018. The spatial and temporal
evolution of the temperature time series are retrieved using the Fisher
Information Measure, which quantifies the information in a signal, and the
Shannon Entropy Power, which is a measure of its uncertainty -- or
unpredictability. The results describe the temporal behaviour of the analysed
variable. Our findings suggest that tropical and temperate zones are now
characterized by higher levels of entropy. Finally, Fisher-Shannon Complexity
is introduced and applied to study the evolution of the daily maximum surface
temperature distributions.Comment: 7 pages, 4 figure
Comparative chromosome painting discloses homologous Segments in distantly related mammals
Comparative chromosome painting, termed ZOO-FISH, using DNA libraries from flow
sorted human chromosomes 1,16,17 and X, and mouse chromosome 11 discloses the
presence of syntenic groups in distantly related mammalian Orders ranging from
primates (Homo sapiens), rodents (Mus musculus), even-toed ungulates (Muntiacus
muntjak vaginalis and Muntiacus reevesi) and whales (Balaenoptera physalus). These
mammalian Orders have evolved separately for 55-80 million years (Myr). We conclude
that ZOO-FISH can be used to generate comparative chromosome maps of a large
number of mammalian species
- …