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1.
ABSTRACT

Past research has consistently reported a higher rate of drug use before arrest among incarcerated inmates than that of the general population. However, there is a lack of either qualitative or quantitative research on this topic under the Chinese setting. Drawing upon survey data collected from 1,518 inmates in a Chinese province, this study attempts to fill in the research gap by assessing the connection between risk factors associated with pre-arrest use. Roughly a quarter of all inmates in the sample had the experience of drug use before arrest. Regression analysis suggested that impulsivity, volatile temper, and perceived prevalence of drug use in neighborhood were significantly related to drug use among inmates. Two control variables include offense type and stable job, were also found to be significant predictors of drug use. Implications for research and policy were highlighted in the end.  相似文献   
2.
ABSTRACT

The illicit drug crops opium and coca are conventionally regarded as sources of instability, an ‘evil’ that breeds fragility and violence. Fragile states are supposed to be most vulnerable to their production and consequent harms. Yet by looking into the local contexts of the world’s leading opium and coca producers – Afghanistan, Myanmar, Colombia and Bolivia – these illicit crops are found to also be sources of stability, even drivers of economic growth. They enable marginalized communities and territories abandoned by the state to be reinserted into national and global markets. Within so-called ‘fragile’ and conflict-affected areas are displaced and dispossessed households adopting innovative and unorthodox strategies for coping and survival in changing and insecure environments. This paper maps out an approach, useful for examining the resilience that has emerged amidst violence and uncertainty in illicit-crop-producing territories, and which can hopefully tackle the continuing disconnect between drugs and development policy.  相似文献   
3.
This paper studies the asymptotic behaviour of the false discovery and non‐discovery proportions of the dynamic adaptive procedure under some dependence structure. A Bahadur‐type representation of the cut point in simultaneously performing a large scale of tests is presented. The asymptotic bias decompositions of the false discovery and non‐discovery proportions are given under some dependence structure. In addition to existing literatures, we find that the randomness due to the dynamic selection of the tuning parameter in estimating the true null rate serves as a source of the approximation error in the Bahadur representation and enters into the asymptotic bias term of the false discovery proportion and those of the false non‐discovery proportion. The theory explains to some extent why some seemingly attractive dynamic adaptive procedures do not outperform the competing fixed adaptive procedures substantially in some situations. Simulations justify our theory and findings.  相似文献   
4.
Various statistical models have been proposed for two‐dimensional dose finding in drug‐combination trials. However, it is often a dilemma to decide which model to use when conducting a particular drug‐combination trial. We make a comprehensive comparison of four dose‐finding methods, and for fairness, we apply the same dose‐finding algorithm under the four model structures. Through extensive simulation studies, we compare the operating characteristics of these methods in various practical scenarios. The results show that different models may lead to different design properties and that no single model performs uniformly better in all scenarios. As a result, we propose using Bayesian model averaging to overcome the arbitrariness of the model specification and enhance the robustness of the design. We assign a discrete probability mass to each model as the prior model probability and then estimate the toxicity probabilities of combined doses in the Bayesian model averaging framework. During the trial, we adaptively allocated each new cohort of patients to the most appropriate dose combination by comparing the posterior estimates of the toxicity probabilities with the prespecified toxicity target. The simulation results demonstrate that the Bayesian model averaging approach is robust under various scenarios. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
5.
The central limit theorem indicates that when the sample size goes to infinite, the sampling distribution of means tends to follow a normal distribution; it is the basis for the most usual confidence interval and sample size formulas. This study analyzes what sample size is large enough to assume that the distribution of the estimator of a proportion follows a Normal distribution. Also, we propose the use of a correction factor in sample size formulas to ensure a confidence level even when the central limit theorem does not apply for these distributions.  相似文献   
6.
In this article, we propose a factor-adjusted multiple testing (FAT) procedure based on factor-adjusted p-values in a linear factor model involving some observable and unobservable factors, for the purpose of selecting skilled funds in empirical finance. The factor-adjusted p-values were obtained after extracting the latent common factors by the principal component method. Under some mild conditions, the false discovery proportion can be consistently estimated even if the idiosyncratic errors are allowed to be weakly correlated across units. Furthermore, by appropriately setting a sequence of threshold values approaching zero, the proposed FAT procedure enjoys model selection consistency. Extensive simulation studies and a real data analysis for selecting skilled funds in the U.S. financial market are presented to illustrate the practical utility of the proposed method. Supplementary materials for this article are available online.  相似文献   
7.
A new estimator for estimating the proportion of a potentially sensitive attribute in survey sampling has been introduced by solving a linear equation. The proposed estimator has been compared with the estimator proposed by Odumade and Singh (2009) with equal protection to all of the respondents. The asymptotic properties of the proposed estimator are investigated through exact numerical illustrations for different choices of parameters. A non randomized response approach has been suggested. A scope for further research has also been pointed out.  相似文献   
8.
中等收入群体的界定标准、规模和特征一直是学术界关注的焦点。在回顾和评述现有各种界定标准的基础上,建议采用全球所有国家收入中位数的67%~200%作为定义我国中等收入群体的上下限。研究发现,近些年我国中等收入群体比重在逐渐提高,从2002年的10%上升到2016年的28.9%,这主要源于我国居民整体收入水平的提高而不是收入分配格局的变化。要扩大我国中等收入群体比重,保持中高速增长至关重要,政策的重点是提“低”而不是限“高”,同时要防范现有的中等收入群体跌落为低收入群体。中等收入群体主要分布在城市地区,收入来源主要是工资性收入,储蓄率偏高,受教育水平明显高于低收入者和贫困人口。中等收入群体的标准下限附近分布着规模客观的低收入者,他们是扩大中等收入者比重的潜在来源,应是政策瞄准的主要对象。  相似文献   
9.
药品安全关乎人民群众生命健康、经济发展、社会稳定和国家安全,一直以来都是政府和全社会关注的热点问题之一。但是,近年来频发的各类药品安全事件,揭露了政府监管缺失、药品检测机制不完善、公众投诉失效等诸多问题。本文考虑了药品检测中存在寻租现象,构建了药品生产企业、第三方药品检测机构和政府监管部门之间的三方演化博弈模型,分析了各参与方策略选择的演化稳定性,探讨了各要素对三方策略选择的影响关系,进一步分析了三方博弈系统中均衡点的稳定性。研究结果表明:1)政府增强奖励、惩罚力度均有助于促进企业生产高药效药品、第三方药品检测机构拒绝寻租的规范行为,但是增大奖励力度将不利于政府自身履行监管职责;2)政府设定合理的奖惩机制必须符合对各方的奖惩之和大于其投机收益的条件,才能保障演化稳定市场环境下的药品安全;3)上级政府对监管部门失职的问责对增强企业生产高药效药品的稳健性具有重要意义;4)提升企业的药品销售收益、增加企业寻租成本也是避免企业生产低药效药品的有效途径。最后,利用Matlab 2020b进行了仿真分析,为政府完善药品监管机制提出了对策与建议。  相似文献   
10.
In this paper, proportion estimators and associated variance estimators are proposed for a binary variable with a concomitant variable based on modified ranked set sampling methods, which are extreme ranked set sampling (ERSS), median ranked set sampling (MRSS), percentile ranked set sampling (Per-RSS) and L ranked set sampling (LRSS) methods. The Monte Carlo simulation study is performed to compare the performance of the estimators based on bias, mean squared error, and relative efficiency for different levels of correlation coefficient, set and cycle sizes under normal and log-normal distributions. Moreover, the study is supported with real data application.  相似文献   
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