112,508 research outputs found
An economic evaluation of the early impact of Aimhigher: excellence challenge on pre-16 outcomes: update to previous analysis
The Aimhigher: Excellence Challenge intervention seeks to encourage more young people to articipate in tertiary education. This paper updates previous estimates of the impact of the programme on the GCSE marks and reported expected school leaving ages, among year 11 pupils. Information from 3 different cohorts is used (whereas the previous analysis had data on the first 2 cohorts). In some schools the second and third cohorts have been exposed to the policy, whereas in others only the third cohort was exposed to the policy. This distinction is used to model the impact of the policy using linear regression analysis. However the lack of a comparison group in Spring 2004 means that the impact of the policy can only be estimated under relatively strong assumptions about the evolution of the impact of the policy across time.
Under the assumption that the policy had the same impact in the original treatment (EiC Phase 1 & 2 areas) in Spring 2004 as in Spring 2003, we find evidence that being part of the Aimhigher: Excellence Challenge programme in the new areas (EiC Phase 3) has led to a 5.2 percentage point increase in the year 11 pupils expecting to leave education at age 20 or over. Although slightly larger, this estimate is not statistically significantly different from the increase of 3.7 percentage points found in the original (EiC Phase 1 & 2) areas. Across both types of area (EiC Phase 1& 2 and EiC Phase 3) we estimate that the average impact of the policy is to increase the percentage of year 11 pupils reporting that they will leave education at age 20 or above by 4.6 percentage points. We also find some evidence of a similar positive impact on GCSE English results, although the impact across other GCSEs is less clear.
While the assumptions made in producing these new estimates are relatively strong it is clear that the analysis of the new data does not contradict the previous estimates (which were reliant on less strong assumptions)
Brane bounce-type configurations in a string-like scenario
Brane world six dimensional scenarios with string like metric has been
proposed to alleviate the problem of field localization. However, these models
have been suffering from some drawbacks related with energy conditions as well
as from difficulties to find analytical solutions. In this work, we propose a
model where a brane is made of a scalar field with bounce-type configurations
and embedded in a bulk with a string-like metric. This model produces a sound
AdS scenario where none of the important physical quantities is infinite. Among
these quantities are the components of the energy momentum tensor, which have
its positivity ensured by a suitable choice of the bounce configurations.
Another advantage of this model is that the warp factor can be obtained
analytically from the equations of motion for the scalar field, obtaining as a
result a thick brane configuration, in a six dimensional context. Moreover, the
study of the scalar field localization in these scenario is done.Comment: 15 pages, 5 figures. To appear in Physics Letters
Measurements of surface impedance of superconductors as a function of frequency in microwave range
We report measurements of the complex resistivity in YBCO and MgB thin
films over a continuous frequency spectrum in the microwave range, making use
of a Corbino disk geometry. The paper mainly focuses on the extraction of the
resistivity from raw data, displaying data analysis procedure and its limits of
validity. We obtain and show resistivity curves as a function of frequency and
temperature denoting a frequency dependent widening of the superconducting
transition.Comment: 12 pages, 7 figures. Extended and revised version of cond-mat/0307143
(2003
A note on black hole entropy, area spectrum, and evaporation
We argue that a process where a fuzzy space splits in two others can be used
to explain the origin of the black hole entropy, and why a "generalized second
law of thermodynamics" appears to hold in the presence of black holes. We reach
the Bekenstein-Hawking formula from the count of the microstates of a black
hole modeled by a fuzzy space. In this approach, a discrete area spectrum for
the black hole, which becomes increasingly spaced as the black hole approaches
the Planck scale, is obtained. We show that, as a consequence of this, the
black hole radiation becomes less and less entropic as the black hole
evaporates, in a way that some information about its initial state could be
recovered.Comment: 4 pages, 2 figure
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