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1.
This article applies a series of concepts from Niklas Luhmann's systems theory in an analysis of modern welfare organisations. The point of departure is that social help in late modern welfare states has become 'polycentric' in that 'help' is today being defined by various different agents: public, voluntary and private care providers. Empirically, this article investigates re-housing work with homeless people, a kind of social work which involves several different welfare organisations. The case study shows how these organisations define themselves by making internal constructions of their surroundings, and how their self-enclosed nature creates a certain 'insensitivity' towards one another. How to coordinate and translate within this 'polyphony' of incomparable observations and values represents a major managerial challenge for present-day social workers.  相似文献   
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The increasing environmental challenges associated with the Global South is potentially associated with the socioeconomic changes amid potential institutional deficiencies such as the weak or inefficient environmental regulation. Thus, this twenty-first century challenge has increasingly necessitated more climate action from the Global South as championed by the developed economies. On this note, examines the environmental aspects of law and order (LO) vis-à-vis legal system and socioeconomic (SE) indexes of the Political Risk Services for a panel of 80 selected Global South countries over the period 1984–2014. Additionally, by employing the economic growth vis-à-vis the Gross Domestic Product per capita (GDPC) as additional explanatory variable, the study employs the more recent experimental techniques of Mean Group Estimator (MG), the Augmented Mean Group Estimator (AMG) and the Common Correlated Effects Mean Group (CCEMG). Importantly, with the more efficient CCEMG, the study found that the strength of the legal system in the Global South (although not statistically significant) is a crucial factor to mitigated carbon emission in the panel countries. However, the study found that an improved socioeconomic condition and economic expansion is detrimental to the Global South’s environmental quality. Furthermore, the Granger causality result implied that each of LO, SE and GDPC exhibits a feedback relationship with carbon emissions. Hence, the study suggests the need for a stronger implementation of environmental regulations through a revitalized legal system and some concerted socioeconomic policies that address poverty and unemployment among other factors.

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A randomized trial allows estimation of the causal effect of an intervention compared to a control in the overall population and in subpopulations defined by baseline characteristics. Often, however, clinical questions also arise regarding the treatment effect in subpopulations of patients, which would experience clinical or disease related events post-randomization. Events that occur after treatment initiation and potentially affect the interpretation or the existence of the measurements are called intercurrent events in the ICH E9(R1) guideline. If the intercurrent event is a consequence of treatment, randomization alone is no longer sufficient to meaningfully estimate the treatment effect. Analyses comparing the subgroups of patients without the intercurrent events for intervention and control will not estimate a causal effect. This is well known, but post-hoc analyses of this kind are commonly performed in drug development. An alternative approach is the principal stratum strategy, which classifies subjects according to their potential occurrence of an intercurrent event on both study arms. We illustrate with examples that questions formulated through principal strata occur naturally in drug development and argue that approaching these questions with the ICH E9(R1) estimand framework has the potential to lead to more transparent assumptions as well as more adequate analyses and conclusions. In addition, we provide an overview of assumptions required for estimation of effects in principal strata. Most of these assumptions are unverifiable and should hence be based on solid scientific understanding. Sensitivity analyses are needed to assess robustness of conclusions.  相似文献   
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A draft addendum to ICH E9 has been released for public consultation in August 2017. The addendum focuses on two topics particularly relevant for randomized confirmatory clinical trials: estimands and sensitivity analyses. The need to amend ICH E9 grew out of the realization of a lack of alignment between the objectives of a clinical trial stated in the protocol and the accompanying quantification of the “treatment effect” reported in a regulatory submission. We embed time‐to‐event endpoints in the estimand framework and discuss how the four estimand attributes described in the addendum apply to time‐to‐event endpoints. We point out that if the proportional hazards assumption is not met, the estimand targeted by the most prevalent methods used to analyze time‐to‐event endpoints, logrank test, and Cox regression depends on the censoring distribution. We discuss for a large randomized clinical trial how the analyses for the primary and secondary endpoints as well as the sensitivity analyses actually performed in the trial can be seen in the context of the addendum. To the best of our knowledge, this is the first attempt to do so for a trial with a time‐to‐event endpoint. Questions that remain open with the addendum for time‐to‐event endpoints and beyond are formulated, and recommendations for planning of future trials are given. We hope that this will provide a contribution to developing a common framework based on the final version of the addendum that can be applied to design, protocols, statistical analysis plans, and clinical study reports in the future.  相似文献   
6.
The visualization of social theory is an important part of the development and communication of our theoretical ideas. While most theorists use figures of some kind, few if any have formal training, or guiding rules or principles for the representation of theory. This has often led to poor visualization efforts, and the visual culture of sociology continues to lag behind the natural sciences. The intent of this paper is to serve as a practical and empirically aided guide for social theorists, by providing insights surrounding the cognitive and perceptual properties of certain elements and figures. Through these properties we identify four major problems in theory visualization: vagueness, reduction, unwanted spatial inferences and unwanted metaphorical inferences. We offer solutions to these problems, and to improving theory visualization more generally. Our hope is that this paper will serve as a resource for more thoughtful and informed visualization for practicing social theorists.  相似文献   
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For a trial with primary endpoint overall survival for a molecule with curative potential, statistical methods that rely on the proportional hazards assumption may underestimate the power and the time to final analysis. We show how a cure proportion model can be used to get the necessary number of events and appropriate timing via simulation. If phase 1 results for the new drug are exceptional and/or the medical need in the target population is high, a phase 3 trial might be initiated after phase 1. Building in a futility interim analysis into such a pivotal trial may mitigate the uncertainty of moving directly to phase 3. However, if cure is possible, overall survival might not be mature enough at the interim to support a futility decision. We propose to base this decision on an intermediate endpoint that is sufficiently associated with survival. Planning for such an interim can be interpreted as making a randomized phase 2 trial a part of the pivotal trial: If stopped at the interim, the trial data would be analyzed, and a decision on a subsequent phase 3 trial would be made. If the trial continues at the interim, then the phase 3 trial is already underway. To select a futility boundary, a mechanistic simulation model that connects the intermediate endpoint and survival is proposed. We illustrate how this approach was used to design a pivotal randomized trial in acute myeloid leukemia and discuss historical data that informed the simulation model and operational challenges when implementing it.  相似文献   
8.
Transport protocols provide reliable, end-to-end communication between a source and a destination in a network. The Transmission Control Protocol (TCP) uses backward error correction, where the destination explicitly returns feedback to the source. Forward error correction (FEC) can also be used for transport; here the source includes enough redundancy in the encoding symbols to allow the destination to decode the message. In this paper, we compare the performance of two transport schemes, TCP and LT, a scheme based on rateless FEC codes, in a wireless ad hoc network when topology-transparent scheduling is used for channel access. These schedules are derived from cover-free families, a type of combinatorial design. They provide a mechanism to guarantee collision-free communication between any two nodes provided that each of the N nodes of the network has at most a specified number D of active (transmitting) neighbours. We find that LT outperforms TCP in more strenuous network conditions. To Frank Hwang on the occasion of his sixty-fifth birthday.  相似文献   
9.
Using data obtained from personal interviews with 647 Southeast Asian refugees in Canada, this study tests hypotheses regarding both the association between perceived racial discrimination and depression, and the roles of coping and ethnic identity in conditioning the nature of the discrimination-depression relation. Refugees who reported that they had experienced racial discrimination had higher depression levels than their counterparts who reported no such experiences. Responding to discrimination through confrontation was not significantly associated with depression. Study findings support the effectiveness of forbearance in diminishing the strength of the association between discrimination and depression. The moderating effect of forbearance was conditioned by the level of ethnic identity: The beneficial effect of forbearance was significantly greater among those holding stronger ethnic identification. Cultural and situational interpretations of the findings are presented.  相似文献   
10.
For the analysis of a time-to-event endpoint in a single-arm or randomized clinical trial it is generally perceived that interpretation of a given estimate of the survival function, or the comparison between two groups, hinges on some quantification of the amount of follow-up. Typically, a median of some loosely defined quantity is reported. However, whatever median is reported, is typically not answering the question(s) trialists actually have in terms of follow-up quantification. In this paper, inspired by the estimand framework, we formulate a comprehensive list of relevant scientific questions that trialists have when reporting time-to-event data. We illustrate how these questions should be answered, and that reference to an unclearly defined follow-up quantity is not needed at all. In drug development, key decisions are made based on randomized controlled trials, and we therefore also discuss relevant scientific questions not only when looking at a time-to-event endpoint in one group, but also for comparisons. We find that different thinking about some of the relevant scientific questions around follow-up is required depending on whether a proportional hazards assumption can be made or other patterns of survival functions are anticipated, for example, delayed separation, crossing survival functions, or the potential for cure. We conclude the paper with practical recommendations.  相似文献   
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