Heterogeneity in Schooling Rates of Return

This paper relaxes the assumption of homogeneous rates of return to schooling by employing nonparametric kernel regression. This approach allows us to examine the differences in rates of return to education both across and within groups. Similar to previous studies we find that on average blacks have higher returns to education than whites, natives have higher returns than immigrants and younger workers have higher returns than older workers. Contrary to previous studies we find that the average gap of the rate of return between white and black workers is larger than previously thought and the gap is smaller between immigrants and natives. We also uncover significant heterogeneity, the extent of which differs both across and within groups. The estimated densities of returns vary across groups and time periods and are often skewed. For example, during the period 1950-1990, at least 5% of whites have negative returns. Finally, we uncover the characteristics common amongst those with the smallest and largest returns to education. For example, we find that immigrants, aged 50-59, are most likely to have rates of return in the bottom 5% of the population.nonparametric, Mincer regressions, rate of return to education

Synaptic nanomodules underlie the organization and plasticity of spine synapses.

Experience results in long-lasting changes in dendritic spine size, yet how the molecular architecture of the synapse responds to plasticity remains poorly understood. Here a combined approach of multicolor stimulated emission depletion microscopy (STED) and confocal imaging in rat and mouse demonstrates that structural plasticity is linked to the addition of unitary synaptic nanomodules to spines. Spine synapses in vivo and in vitro contain discrete and aligned subdiffraction modules of pre- and postsynaptic proteins whose number scales linearly with spine size. Live-cell time-lapse super-resolution imaging reveals that NMDA receptor-dependent increases in spine size are accompanied both by enhanced mobility of pre- and postsynaptic modules that remain aligned with each other and by a coordinated increase in the number of nanomodules. These findings suggest a simplified model for experience-dependent structural plasticity relying on an unexpectedly modular nanomolecular architecture of synaptic proteins

Coupling Control Variates for Markov Chain Monte Carlo

We show that Markov couplings can be used to improve the accuracy of Markov chain Monte Carlo calculations in some situations where the steady-state probability distribution is not explicitly known. The technique generalizes the notion of control variates from classical Monte Carlo integration. We illustrate it using two models of nonequilibrium transport

Assembling life history narratives from quantitative longitudinal panel data: what’s the story for families using social work?

Embedded within quantitative longitudinal panel or cohort studies is narrative potential that is arguably untapped but might enrich our understanding of individual and social lives across time. This paper discusses a methodology to assemble the life history narratives of families using social work by drawing on quantitative data from the British Household Panel Survey. It explores whether this person-centred approach helps us to understand the counterintuitive results of a parallel multivariate analyses, which suggest that families using social work fare worse than similar others over time. Our findings are tentative, due to the experimental use of this narrative method and the limits of social work information in the dataset. Nonetheless, the life histories presented bring to light complexities, diversity and the non-linear pathways between families’ needs, support and outcomes that the aggregates obscure. We conclude that reconstructing families’ lives in this way, especially in the absence of complementary longitudinal qualitative data, affords the wider opportunity to interrogate and better understand the findings of quantitative longitudinal studies

Metastable states of a driven flux lattice in a superconductor with strong pins

The flux lattice driven by a uniform driving force in a superconductor with hot, strong, sharp and randomly distributed pinning centers, with applied magnetic field half the matching field is simulated. At low temperature both a non activated regime, where flux motion occurs within a robust percolative flux flow channel, and an activated regime are obtained depending on the sample preparation. These two regimes exhibit distinct resistivity and magnetic induction. In the non activated regime, a clear fingerprint is observed in the autocorrelation function of the longitudinal resitivity, which oscillates at a frequency close to the inverse lattice diffusion time.Comment: 6 figure

Le Grand Henderson Correspondence

Entries include letters, a newspaper clipping of Le Grand\u27s obituary, and a letter written on Abingdon-Cokesbury Press stationery

PROCESOS PARTICIPATIVOS PARA GENERACIÓN DE INNOVACIONES AGROECOLÓGICAS: EL CASO DEL ASENTAMIENTO EPÉ TIARAJU RIBEIRÃO PRETO, BRASIL

N° ISBN - 978-2-7380-1284-5International audienceParticipatory processes for generation of agroecological innovations: the case of settlement Epé Tiaraju Ribeirão Preto, Brasil. - The region of Ribeirão Preto, in north of the state of São Paulo, Brazil, is characterized by the predominance of sugarcane monoculture, with large environmental, social and concentration of land impacts. In response to social demands of the MST - the Movement of Rural Landless Workers, in 2004 was implanted in the region a land reform settlement, backed by the agroecological matrix and the use of agroforestry systems. Since 2005, research activities and socio-environmental training were developed by federal government agencies in support of the settlement. The article discusses the first results of this process of building a new development model for the region, more sustainable under the ecological point of view and allowing regional agrobiodiversity rescue. The data show that the basic training conducted by peasant organizations, coupled with public policies to promote the agroforestry, have led to significant strides in the direction of agroecological transition. In this participatory process of innovation, farmers assume the role of major actors towards sustainable development, because while producing food, conserve biodiversity