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Muheim, R., Phillips, J. B., & Akesson, S. (2006). Polarized light cues underlie compass calibration in migratory songbirds. Science, 313(5788), 837–839.
Abstract: Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunrise and sunset. We suggest that skylight polarization patterns are used to derive an absolute (i.e., geographic) directional system that provides the primary calibration reference for all of the compasses of migratory songbirds.
Xavier Kerola, D. (2006). Modelling artificial night-sky brightness with a polarized multiple scattering radiative transfer computer code: Modelling artificial night-sky brightness. Monthly Notices of the Royal Astronomical Society, 365(4), 1295–1299.
Abstract: As part of an ongoing investigation of radiative effects produced by hazy atmospheres, computational procedures have been developed for use in determining the brightening of the night sky as a result of urban illumination. The downwardly and upwardly directed radiances of multiply scattered light from an offending metropolitan source are computed by a straightforward Gauss-Seidel (G-S) iterative technique applied directly to the integrated form of Chandrasekhar's vectorized radiative transfer equation. Initial benchmark night-sky brightness tests of the present G-S model using fully consistent optical emission and extinction input parameters yield very encouraging results when compared with the double scattering treatment of Garstang, the only full-fledged previously available model.
Fouquet, R., & Pearson, P. J. (2006). Seven centuries of energy services: The price and use of light in the United Kingdom (1300-2000). Energy Journal, 27, 139–177.
Abstract: Before the mid-eighteenth century, most people lived in near-complete
darkness except in the presence of sunlight and moonlight. Since then, the provision
of artificial light has been revolutionised by a series of innovations in appliances,
fuels, infrastructures and institutions that have enabled the growing demands of
economic development for artificial light to be met at dramatically lower costs:
by the year 2000, while United Kingdom GDP per capita was 15 times its 1800
value, lighting services cost less than one three thousandth of their 1800 value,
per capita use was 6,500 times greater and total lighting consumption was 25,000
times higher than in 1800. The economic history of light shows how focussing on
developments in energy service provision rather than simply on energy use and
prices can reveal the âtrueâ declines in costs, enhanced levels of consumption
and welfare gains that have been achieved. While emphasising the value of past
experience, the paper also warns against the dangers of over-reliance on past
trends for the long-run forecasting of energy consumption given the potential for the
introduction of new technologies and fuels, and for rebound and saturation effects.
Marchant, P. R. (2006). Investigating whether a crime reduction measure works. Radical Statistics, 91.
Abstract: Crime is a serious business. It causes great distress and fear. It costs a lot
to deal with its consequences. In these regards crime shares much with
the problem of ill-health and disease. The application of sound science and
statistics has allowed great strides to be made in dealing with problems of
ill health. Medical statistics is one of the recognised, established
disciplines involved in researching healthcare.
The parallels between research in crime reduction and in healthcare do
appear to differ in terms of quality. Although there is still room for
considerable improvement in researching health-care, an investigation
into the underpinning of statistical methods used indicates that the
problems are substantially worse in the study of crime. The consideration
given to statistics in crime studies seems rather flimsy, yet important
claims are made which are statistical at source and may affect policy, and
so can have considerable costs attached. Therefore, for example, it is
important to know whether the underlying crime level has really changed,
rather than just being the result of perhaps sampling variation or some
artefact giving rise to statistical bias or systematic error. This is necessary
when trying to determine whether a Crime Reduction Intervention (CRI)
has actually worked.
I started examining the scientific basis of the claim for the effectiveness for
one particular CRI, basically because I was concerned about negative side
effects and I thought the claim implausible. I remain concerned and
unconvinced. The statistical issues and concerns I raise apply also to
investigating other CRIs and to existing published analyses.
This piece extends work presented in Marchant (2006); earlier work on the
statistical issues involved can be found in Marchant (2005a, b; 2004).
Rich, C., Longcore, T., & editors. (2006). Ecological Consequences of Artificial Night Lighting. Island Press., .