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351.
Using relative utility curves to evaluate risk prediction 总被引:2,自引:0,他引:2
Stuart G. Baker Nancy R. Cook rew Vickers Barnett S. Kramer 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2009,172(4):729-748
Summary. Because many medical decisions are based on risk prediction models that are constructed from medical history and results of tests, the evaluation of these prediction models is important. This paper makes five contributions to this evaluation: the relative utility curve which gauges the potential for better prediction in terms of utilities, without the need for a reference level for one utility, while providing a sensitivity analysis for misspecification of utilities, the relevant region, which is the set of values of prediction performance that are consistent with the recommended treatment status in the absence of prediction, the test threshold, which is the minimum number of tests that would be traded for a true positive prediction in order for the expected utility to be non-negative, the evaluation of two-stage predictions that reduce test costs and connections between various measures of performance of prediction. An application involving the risk of cardiovascular disease is discussed. 相似文献
352.
The reversible jump Markov chain Monte Carlo (MCMC) sampler (Green in Biometrika 82:711–732, 1995) has become an invaluable device for Bayesian practitioners. However, the primary difficulty with the sampler lies with the
efficient construction of transitions between competing models of possibly differing dimensionality and interpretation. We
propose the use of a marginal density estimator to construct between-model proposal distributions. This provides both a step
towards black-box simulation for reversible jump samplers, and a tool to examine the utility of common between-model mapping
strategies. We compare the performance of our approach to well established alternatives in both time series and mixture model
examples. 相似文献
353.
Given that savings behaviour and worker productivity have strong life-cycle components and given that demographic profiles
vary across countries, population age structure should be linked to differences in levels of economic development. In this
paper, we measure the economic importance of age structure variation for the global economy. We find that demographic maturation
has been associated with nearly half of the evolution of global per capita GDP since 1960. We also find that age structure
differences can account for just over half of the variation in worldwide per capita GDP (i.e. the lack of sigma convergence)
observed since 1960.
相似文献
Pablo Hernández de Cos (Corresponding author)Email: |
354.
Dorothea Jansen Richard Heidler Regina von Görtz 《KZfSS K?lner Zeitschrift für Soziologie und Sozialpsychologie》2009,61(3):463-467
The article “Emergence of an academic elite? The impact of universities’ size and reputation on research funding” by Katrin Auspurg, Thomas Hinz and Jürgen Güdler (volume 4/2008 of this Journal) discusses critically Richard Münch’s thesis of monopolistic tendencies in the German science system. Unfortunately the authors focus in their analysis on an improper object, the “Individual grants programme” (Normalverfahren) of the German Research Foundation (DFG). However, problematic developments for the German science system will rather result from the “Coordinated grants programmes” (koordinierte Programme), in particular the excellence initiative. Furthermore the authors fail to connect their analysis to the broader context of the functions and implications of the increasing role of third party funding in the German science system. 相似文献
355.
Katrin Auspurg Thomas Hinz Jürgen Güdler 《KZfSS K?lner Zeitschrift für Soziologie und Sozialpsychologie》2009,61(3):469-474
We reply to the critical comments of Richard Münch and the author group Jansen, Heidler and von Goetz on our article “Emergence of an Academic Elite? The Impact of Universities’ Size and Reputation on Research Funding” published in this journal. After reviewing some other sociologists’ statements on Münch’s thesis about the academic elite we reinforce the gain of our empirical analyses of hypotheses of the sociology of science in general, on the Matthew-Effect, and on trends to a possible cartelization and monopolization in the German science system. The main critic of unsuited data (we used applications for single grants submitted to the German Research Foundation) does not adequately consider the postulated scope of the investigated theses and our analyses do not aim at a general evaluation of the “Initative of Excellence”. 相似文献
356.
David G. Phillips 《Clinical Social Work Journal》2009,37(1):1-6
As clinical social work developed in America it was highly influenced by the concepts and techniques of psychoanalysis and
many of its practitioners became interested in seeking psychoanalytic training. More and more psychoanalysts are now coming
from a background in clinical social work due to the development of a network of interdisciplinary training institutes and
the opening of the Institutes of the American Psychoanalytic Association to non-medical candidates. This special issue considers
how psychoanalysis may be affected as more of its practitioners and contributors come from a background in clinical social
work. This introduction reviews the history of the development of clinical social work and outlines the issues related to
“lay analysis” in this country.
相似文献
David G. PhillipsEmail: |
357.
Thomas G. Koch 《Journal of Labor Research》2009,30(4):340-349
Employer-provided insurance is the leading source of medical insurance for non-elderly Americans. However, it leaves many
without coverage. Evidence suggests that the non-group insurance market does a poor job of filling in these gaps, for those
with both short- and long-term uninsurance. It does so for all income and age groups, as well as for both genders. It does
fill some of the gaps in employer-provided coverage for those with middle and high incomes, though very incompletely. 相似文献
358.
This article employs the process of critical reflection to uncover and challenge the hegemonic assumptions of evidence-based practice (EBP). The critical reflection process results in a re-conceptualisation of best practices that, while still honouring empirical research, is less hierarchical and more inclusive of a broad spectrum of interests than traditional EBP. Multidimensional Evidence-Based Practice (MEBP) validates consumer wisdom, professional experience, and qualitative research as equal partners to quantitative research in determining current state-of-the art best practices. Furthermore, MEBP incorporates a value-critical analysis of those best practices that can lead to improvements and innovations, so that ‘best practices’ becomes a dynamic rather than a static construct. 相似文献
359.
Edgar G. Karapetyan Anna A. Atoyan Marta E. Sandoyan Demeh Daradkah 《Transition Studies Review》2009,16(2):287-298
During the modern phase of economic reforms directed at the establishment of market economy, many countries with transition
economies face the challenge of solving the issue of formation and rational usage of internal sources of financing the real
sector of the economy, as well as attracting considerable volume of direct foreign investment. In general, financial market
imperfections hold back innovation and growth, and that public policy can complement financial markets. Therefore, the most
relevant issue at the present time is the formation of attendant and complex supervision institutions, as well as an exigency
of innovative economy governance as mainframe principles for further banking system elaboration and financial sector development
in general. We have taken Armenia as a case study for transition economy as far as Armenia is currently in the stage of capital
market development through integration into international financial markets.
相似文献
360.
Landscape urbanization threatens plant phylogenetic diversity in the Brazilian Atlantic Forest 总被引:1,自引:0,他引:1
Valdecir Silva-Junior Danielle G. Souza Rubens T. Queiroz Luiz G. R. Souza Elâine M. S. Ribeiro Bráulio A. Santos 《Urban Ecosystems》2018,21(4):625-634
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation. 相似文献