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231.
Gambling studies have described a “near-miss effect” wherein the experience of almost winning increases gambling persistence. The near-miss has been proposed to inflate the value of preceding actions through its perceptual similarity to wins. We demonstrate here, however, that it acts as a conditioned stimulus to positively or negatively influence valuation, dependent on reward expectation and cognitive engagement. When subjects are asked to choose between two simulated slot machines, near-misses increase valuation of machines with a low payout rate, whereas they decrease valuation of high payout machines. This contextual effect impairs decisions and persists regardless of manipulations to outcome feedback or financial incentive provided for good performance. It is consistent with proposals that near-misses cause frustration when wins are expected, and we propose that it increases choice stochasticity and overrides avoidance of low-valued options. Intriguingly, the near-miss effect disappears when subjects are required to explicitly value machines by placing bets, rather than choosing between them. We propose that this task increases cognitive engagement and recruits participation of brain regions involved in cognitive processing, causing inhibition of otherwise dominant systems of decision-making. Our results reveal that only implicit, rather than explicit strategies of decision-making are affected by near-misses, and that the brain can fluidly shift between these strategies according to task demands.  相似文献   
232.
Despite the increased attention, which has been given to the issue of involving knowledge and experts from the social sciences and humanities (SSH) into the products and works of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), little is known on what the expectations towards the involvement of SSH in IPBES actually are. The aim of this paper is to close this gap by identifying the range of possible SSH contributions to IPBES that are expected in the literature, and discuss the inherent challenges of and concrete ways to realize these contributions in the particular institutional setting of IPBES. We address these two points by: firstly, assessing the literature dealing with IPBES and building a typology describing the main ways in which contributions from SSH to IPBES have been conceived between 2006 and 2017. We discuss these expected contributions in light of broader debates on the role of SSH in nature conservation and analyse some of the blind spots and selectivities in the perception of how SSH could substantially contribute to the works of IPBES. Then, secondly, by looking at one particular example, economics and its use in the first thematic assessment on pollinators, pollination and food production, we will concretely illustrate how works in a given discipline could contribute in many different and unprecedented ways to the works of IPBES and help identify paths for enhancing the conservation of biodiversity. Finally, we propose a range of practical recommendations as to how to increase the contribution of SSH in the works of IPBES.  相似文献   
233.
Personal wealth has grown since the 1970s twice as fast in real terms as national income. Has this rise in the wealth-income ratio led to a corresponding increase in the wealth being passed on from one generation to the next? Are we returning to the levels of inheritance found in the 19th century? The aim of this paper is to construct UK evidence on the extent of the transmission of wealth in the form of estates and gifts inter vivos. It takes a long-run view of inheritance, starting from 1896, when the modern Estate Duty was introduced, and exploits the extensive estate data published over the years. Construction of a long-run time series for more than a century is challenging, and there are important limitations. The resulting time-series demonstrates the major importance of inheritance in the UK before the First World War, when the total transmitted wealth represented some 20 per cent of net national income. In the inter-war period, the total was around 15 per cent, falling to some 10 per cent after the Second World War, and then falling further to below 5 per cent in the late 1970s. Since then, there has indeed been an upturn: a rise from 4.8 per cent in 1977 to 8.2 per cent in 2006. This increase was more or less in line with the increase in personal wealth, and has to be interpreted in the light of the changing net worth of the corporate and public sectors of the economy.  相似文献   
234.
Public debates about the rise in top income shares often focus on the growing dispersion in earnings, and the soaring pay for top executives and financial-sector employees. But can the change in the marginal distribution of earnings on its own explain the rise in top income shares? Are top executives replacing capital owners in the group of top-income earners, or are we rather witnessing a fusion of top capital and top earnings? This paper proposes an extension of the copula framework and uses it for exploring the changing composition of top incomes. It illustrates that changes in top income shares can easily be decomposed into respective changes in the marginal distributions of labour and capital income and the changing association between the two types of income. An application using tax record data from Norway shows that the association between top labour and capital incomes grew stronger between 1995 and 2005 in the top half of the wage and capital income distribution, though it declined for the top 1% of capital income receivers. A gender decomposition demonstrates that the association of wage and capital incomes at the top is particularly striking for men, whilst women are largely under-represented in the top halves of the two marginal distributions.  相似文献   
235.
This study proposes a synthetic double sampling s chart that integrates the double sampling (DS) s chart and the conforming run length chart. An optimization procedure is proposed to compute the optimal parameters of the synthetic DS s chart. The performance of the synthetic DS s chart is compared with other existing control charts for monitoring process standard deviation. The results show that the synthetic DS s chart is more effective for detecting increases in the process standard deviation for a wide range of shifts. An example is provided to illustrate the operation procedure of the synthetic DS s chart.  相似文献   
236.
In drug development, it sometimes occurs that a new drug does not demonstrate effectiveness for the full study population but appears to be beneficial in a relevant subgroup. In case the subgroup of interest was not part of a confirmatory testing strategy, the inflation of the overall type I error is substantial and therefore such a subgroup analysis finding can only be seen as exploratory at best. To support such exploratory findings, an appropriate replication of the subgroup finding should be undertaken in a new trial. We should, however, be reasonably confident in the observed treatment effect size to be able to use this estimate in a replication trial in the subpopulation of interest. We were therefore interested in evaluating the bias of the estimate of the subgroup treatment effect, after selection based on significance for the subgroup in an overall “failed” trial. Different scenarios, involving continuous as well as dichotomous outcomes, were investigated via simulation studies. It is shown that the bias associated with subgroup findings in overall nonsignificant clinical trials is on average large and varies substantially across plausible scenarios. This renders the subgroup treatment estimate from the original trial of limited value to design the replication trial. An empirical Bayesian shrinkage method is suggested to minimize this overestimation. The proposed estimator appears to offer either a good or a conservative correction to the observed subgroup treatment effect hence provides a more reliable subgroup treatment effect estimate for adequate planning of future studies.  相似文献   
237.
A common objective of cohort studies and clinical trials is to assess time-varying longitudinal continuous biomarkers as correlates of the instantaneous hazard of a study endpoint. We consider the setting where the biomarkers are measured in a designed sub-sample (i.e., case-cohort or two-phase sampling design), as is normative for prevention trials. We address this problem via joint models, with underlying biomarker trajectories characterized by a random effects model and their relationship with instantaneous risk characterized by a Cox model. For estimation and inference we extend the conditional score method of Tsiatis and Davidian (Biometrika 88(2):447–458, 2001) to accommodate the two-phase biomarker sampling design using augmented inverse probability weighting with nonparametric kernel regression. We present theoretical properties of the proposed estimators and finite-sample properties derived through simulations, and illustrate the methods with application to the AIDS Clinical Trials Group 175 antiretroviral therapy trial. We discuss how the methods are useful for evaluating a Prentice surrogate endpoint, mediation, and for generating hypotheses about biological mechanisms of treatment efficacy.  相似文献   
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A college of social work developed a partnership with a state commission on indigent defense to examine existing data-collection procedures, potential case outcomes, and practical implications of implementing holistic defense programs. The holistic defense model responds to the complex challenges of justice-system-involved defendants by providing social services in public defense offices. Using chi-square and logistic regression analyses of administrative data for a sample of 15,994 public defendants from a single judicial circuit, this research study examined case outcomes before and after implementation of a holistic defense program. Results were mixed regarding effectiveness of holistic defense in mitigating the effect of justice involvement for indigent defendants. Implementation of holistic defense was associated with a decrease in case dismissals. However, defendants receiving holistic representation were less likely to be indicted than defendants prior to program implementation. Once indicted, there were no changes in levels of diversions, and more defendants were held on bond, convicted as guilty, and incarcerated. After program implementation, fewer defendants were sentenced to alternatives to incarceration; more defendants were sentenced to time served, avoiding further incarcerative penalty. These findings suggested the need for further research to determine whether holistic defense practices are producing desired legal and social service outcomes.  相似文献   
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