9,061 research outputs found
Intergenerational income mobility. Access to top jobs, the low-pay no-pay cycle and the role of education in a common framework
Studies of intergenerational mobility have typically focused on estimating the average
persistence across generations. Here, we use the relatively new unconditional quantile
regression technique to consider how intergenerational persistence varies across the
distribution of sons’ earnings.We find a J-shaped relationship between parental income
and sons’ earnings, with parental income a strong predictor of labour market success
for those at the bottom, and to an even greater extent, the top of the earnings
distribution. We explore the role early skills, education and early labour market
attachment in shaping this pattern for the first time. Worryingly, we find that the
association with childhood parental income dominating that of a high level of education
at the top of the distribution of earnings. In this sense, education is not as meritocratic as
we might hope, as those with the same detailed educational attainment still see a strong
association between their earnings and their parental income. Early labour market spells
out of work have lasting effects on those at the bottom, alongside parental income
Real and imaginary-time quarkonium correlators in a hot plasma
The possibility of describing the behavior of a pair in a hot
plasma in terms of an effective potential is investigated. It is shown that as
long as medium effects can be embodied in a gaussian action, like in the QED
case, the propagator obeys a closed temporal evolution equation
whose large-time behavior is governed by an effective potential. The latter,
beside screening, displays also an imaginary part related to collisions.Comment: Talk given at the 8-th Conference "Quark Confinement and the Hadron
Spectrum", Mainz, Germany, 1-6 September 200
Exploring the experiences and outcomes of advantaged and disadvantaged families
This report provides further evidence of the interrelationship between age, young motherhood, family type and a range of measures of socio-economic advantage and disadvantage. Maternal age and family type were found to be closely interrelated and both strongly associated with socio-economic disadvantage, with concentrated disadvantage evident in mothers under 25 and lone parents who do not live with other adults. These measures were also closely associated with health-related behaviours including likelihood of breastfeeding, attending ante-natal classes and smoking amongst mothers. Even amongst more disadvantaged groups, positive health-related behaviours were connected to relative social and economic advantage with level of maternal education featuring prominently
HIV testing intervention development among men who have sex with men in the developed world
HIV testing is a ‘gateway’ technology, enabling access to treatment and HIV prevention. Biomedical approaches to prevention, such as pre-exposure prophylaxis and treatment as prevention, require accurate and regular HIV test results. HIV testing also represents a powerful ‘teachable moment’ for behavioural prevention. An increasing range of HIV tests and the emergence of self-managed diagnostic technologies (e.g. self-testing) means there is now considerable diversification of when, where and how results are available to those who test. These changes have profound implications for intervention development and, indeed, health service redesign. This paper highlights the need for better ways of conceptualising testing in order to capitalise on the health benefits that diverse HIV testing interventions will bring. A multidimensional framework is proposed to capture ongoing developments in HIV testing among men who have sex with men and focus on the intersection of: (1) the growing variety of HIV testing technologies and the associated diversification of their pathways into care; (2) psychosocial insights into the behavioural domain of HIV testing; and (3) better appreciation of population factors associated with heterogeneity and concomitant inequities. By considering these three aspects of HIV testing in parallel, it is possible to identify gaps, limitations and opportunities in future HIV testing-related interventions. Moreover, it is possible to explore and map how diverse interventions may work together having additive effects. Only a holistic and dynamic framework that captures the increasing complexity of HIV testing is fit for purpose to deliver the maximum public health benefit of HIV testing
The star cluster system of the 3 Gyr old merger remnant NGC 1316: Clues from optical and near-infrared photometry
The giant merger remnant galaxy NGC 1316 (Fornax A) is an ideal probe for
studying the long-term effects of a past major merger on star cluster systems,
given its spectroscopically derived merger age of ~3 Gyr which we reported in a
recent paper. Here we present new ground-based, large-area optical and near-IR
imaging of star clusters in NGC 1316, complemented with deep HST/WFPC2 imaging.
We find that the optical-near-IR colours and luminosities of the brightest ~10
clusters in NGC 1316 are consistent with those of intermediate-age (2-3 Gyr)
populations. Unlike `normal' giant ellipticals, the B-I colour distribution of
clusters in NGC 1316 is not clearly bimodal. However, the luminosity functions
(LFs) of the blue and red parts of the cluster colour distribution are
different: The red cluster LF is well represented by a power law with index
-1.2 +/- 0.3, extending to about 1.5 mag brighter (in B) than those of typical
giant ellipticals. In contrast, the shape of the blue cluster LF is consistent
with that of `normal' spiral and elliptical galaxies. We conclude that the star
cluster system of NGC 1316 is a combination of a population of age ~3 Gyr
having roughly solar metallicity and a population of old, metal-poor clusters
which probably belonged to the pre-merger galaxies. After the 3 Gyr old,
metal-rich clusters fade to an age of 10 Gyr, they will form a red `peak' in a
bimodal cluster colour distribution. This `red peak' will have a colour
consistent with that found in `normal, old' giant ellipticals of the same
galaxy luminosity (taking age dimming into account). These features of the star
cluster system of NGC 1316 are fully consistent with scenarios for forming
`normal' giant elliptical galaxies through gas-rich mergers at look-back times
\ga 10 Gyr.Comment: 21 pages, LaTeX format, figures included using psfig.sty. Accepted by
MNRAS. Abstract below is abridged (full abstract in paper). Used 8-bit
mapping to limit size of figures (24-bit mapping in MNRAS paper
An Ontology-Based Recommender System with an Application to the Star Trek Television Franchise
Collaborative filtering based recommender systems have proven to be extremely
successful in settings where user preference data on items is abundant.
However, collaborative filtering algorithms are hindered by their weakness
against the item cold-start problem and general lack of interpretability.
Ontology-based recommender systems exploit hierarchical organizations of users
and items to enhance browsing, recommendation, and profile construction. While
ontology-based approaches address the shortcomings of their collaborative
filtering counterparts, ontological organizations of items can be difficult to
obtain for items that mostly belong to the same category (e.g., television
series episodes). In this paper, we present an ontology-based recommender
system that integrates the knowledge represented in a large ontology of
literary themes to produce fiction content recommendations. The main novelty of
this work is an ontology-based method for computing similarities between items
and its integration with the classical Item-KNN (K-nearest neighbors)
algorithm. As a study case, we evaluated the proposed method against other
approaches by performing the classical rating prediction task on a collection
of Star Trek television series episodes in an item cold-start scenario. This
transverse evaluation provides insights into the utility of different
information resources and methods for the initial stages of recommender system
development. We found our proposed method to be a convenient alternative to
collaborative filtering approaches for collections of mostly similar items,
particularly when other content-based approaches are not applicable or
otherwise unavailable. Aside from the new methods, this paper contributes a
testbed for future research and an online framework to collaboratively extend
the ontology of literary themes to cover other narrative content.Comment: 25 pages, 6 figures, 5 tables, minor revision
IntRepair: Informed Repairing of Integer Overflows
Integer overflows have threatened software applications for decades. Thus, in
this paper, we propose a novel technique to provide automatic repairs of
integer overflows in C source code. Our technique, based on static symbolic
execution, fuses detection, repair generation and validation. This technique is
implemented in a prototype named IntRepair. We applied IntRepair to 2,052C
programs (approx. 1 million lines of code) contained in SAMATE's Juliet test
suite and 50 synthesized programs that range up to 20KLOC. Our experimental
results show that IntRepair is able to effectively detect integer overflows and
successfully repair them, while only increasing the source code (LOC) and
binary (Kb) size by around 1%, respectively. Further, we present the results of
a user study with 30 participants which shows that IntRepair repairs are more
than 10x efficient as compared to manually generated code repairsComment: Accepted for publication at the IEEE TSE journal. arXiv admin note:
text overlap with arXiv:1710.0372
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