5,970 research outputs found
Overlaps in dimensions of poverty
The Poverty and Social Exclusion Survey of Britain made it possible first time to explore poverty using three different measures applied at the same time on the same sample. The measures were: lacking socially perceived necessities; being subjectively poor and having a relatively low income. These approaches are all commonly used to identify the poor and to measure poverty but rarely if ever in combination. In this article we have found that there is little overlap in the group of people defined as poor by these dimensions. There are reasons for this lack of overlap, connected to the reliability and validity of the different measures. However the people who are defined as living in poverty by different measures of poverty are different. This inevitably means that the policy response to poverty will be different depending on which measure is employed. We have attempted to analyse overlap in two ways. First, by exploring the dimensions of poverty cumulatively, we have found that, the more dimensions people are poor on, the more they are unlike the non-poor and the poor on only one dimension, in their characteristics and in their social exclusion. Second, by treating particular dimensions as meriting more attention than others, we explored three permutations of this type and concluded that, while each permutation were more unlike the non-poor than those poor on a single dimension, they were not as unlike the non-poor as the cumulatively poor were. These results indicate that accumulation might be a better way of using overlapping measures of poverty than by giving priority to one dimension over another. The implication of the paper is that it is not safe to rely on one measure of poverty –the results obtained are just not reliable enough. Surveys, such as the Family Resources Survey or the European Community Household Panel, which are used to monitor the prevalence of poverty, need to be adapted to enable results to be triangulated – to incorporate a wider range of poverty measures
Universal inversion formulas for recovering a function from spherical means
The problem of reconstruction a function from spherical means is at the heart
of several modern imaging modalities and other applications. In this paper we
derive universal back-projection type reconstruction formulas for recovering a
function in arbitrary dimension from averages over spheres centered on the
boundary an arbitrarily shaped smooth convex domain. Provided that the unknown
function is supported inside that domain, the derived formulas recover the
unknown function up to an explicitly computed smoothing integral operator. For
elliptical domains the integral operator is shown to vanish and hence we
establish exact inversion formulas for recovering a function from spherical
means centered on the boundary of elliptical domains in arbitrary dimension.Comment: [20 pages, 2 figures] Compared to the previous versions I corrected
some typo
The longest excursion of stochastic processes in nonequilibrium systems
We consider the excursions, i.e. the intervals between consecutive zeros, of
stochastic processes that arise in a variety of nonequilibrium systems and
study the temporal growth of the longest one l_{\max}(t) up to time t. For
smooth processes, we find a universal linear growth \simeq
Q_{\infty} t with a model dependent amplitude Q_\infty. In contrast, for
non-smooth processes with a persistence exponent \theta, we show that <
l_{\max}(t) > has a linear growth if \theta
\sim t^{1-\psi} if \theta > \theta_c. The amplitude Q_{\infty} and the exponent
\psi are novel quantities associated to nonequilibrium dynamics. These
behaviors are obtained by exact analytical calculations for renewal and
multiplicative processes and numerical simulations for other systems such as
the coarsening dynamics in Ising model as well as the diffusion equation with
random initial conditions.Comment: 4 pages,2 figure
Short communications: Should the Brown-headed Apalis Apalis alticola be on the Kenya list?
No abstrac
Reconstruction of deglacial sea surface temperatures in the tropical Pacific from selective analysis of a fossil coral
The Sr/Ca of coral skeletons demonstrates potential as an indicator of sea surface temperatures (SSTs). However, the glacial-interglacial SST ranges predicted from Sr/Ca of fossil corals are usually higher than from other marine proxies. We observed infilling of secondary aragonite, characterised by high Sr/Ca ratios, along intraskeletal pores of a fossil coral from Papua New Guinea that grew during the penultimate deglaciation (130 +/- 2 ka). Selective microanalysis of unaltered areas of the fossil coral indicates that SSTs at similar to 130 ka were <= 1 degrees C cooler than at present in contrast with bulk measurements ( combining infilled and unaltered areas) which indicate a difference of 6-7 degrees C. The analysis of unaltered areas of fossil skeletons by microprobe techniques may offer a route to more accurate reconstruction of past SSTs.</p
Grothendieck's constant and local models for noisy entangled quantum states
We relate the nonlocal properties of noisy entangled states to Grothendieck's
constant, a mathematical constant appearing in Banach space theory. For
two-qubit Werner states \rho^W_p=p \proj{\psi^-}+(1-p){\one}/{4}, we show
that there is a local model for projective measurements if and only if , where is Grothendieck's constant of order 3. Known bounds
on prove the existence of this model at least for ,
quite close to the current region of Bell violation, . We
generalize this result to arbitrary quantum states.Comment: 6 pages, 1 figur
EFFECTS OF AN ANGLED STARTING BLOCK ON SPRINT START KINEMATICS
The sprint start mechanics have changed over the years with the invention of the starting blocks. The most recent modification of the starting block developed by Gill Athletics was to create an outward angle of the foot position in the block in order to match the .28 rad. (16 deg.) oblique axis of the ankle. This study examined the effects of an outward angled foot position in a starting block prototype on the first four steps during sprinting kinematics
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