陕西省人口城市化Logistic模型及其应用——基于结构突变的理论分析

城市化是走向现代化的必经阶段,准确的城市化预测是进行经济、社会建设的基础。在结构突变理论的基础上,用Logistic模型对1978～2010年陕西城市化率进行分析。结论表明：1999年为陕西城市化率的结构突变点,说明城市化率的增长受到外部冲击的影响,分段以后的拟合优度明显提高。分别以阈值0.8和1进行分阶段构建的Logistic拟合精度明显提高,但阈值为1的精度更高,说明陕西城市化还在加速,预测表明到2030年陕西城市化率将达到70%左右。总体而言,从1984年到2030年为陕西省城市化的加速阶段。城市化加速阶段的住房问题、人口膨胀、环境恶化、交通拥挤、社会治安问题必须妥善解决。     

Strategies for fostering basic psychological needs support in high quality youth leadership programs

Youth leadership programming has become an increasingly common context to foster basic psychological needs and promote youth development. The purpose of this qualitative study was to explore strategies involved in fostering youth needs support within six leadership programs. Two leaders and 30 youth participated in semi-structured interviews to better understand the strategies used to foster needs support. Findings revealed that leaders were able to foster a sense of relatedness among youth through building trusting adult-youth relationships and nurturing an inclusive environment. Maximizing choice and negotiating youth voice helped to foster youth’s autonomy. Finally, creating a task-oriented climate and providing intentional opportunities for skill-building helped to foster youth’s competence. Findings suggest that training for leaders is critical in understanding what, and how strategies should be employed to help foster youth needs support in leadership programming. Limitations and future directions are outlined.     

基于语言磨蚀理论视角下的维吾尔族大学生英语教学

20世纪80年代在语言磨蚀领域已有相关理论形成,基于此领域中的回归假说、语言干扰、关键阈值、语言提取失败和语言的动态系统理论,依据维吾尔族大学生特殊的英语学习现状,据此得出母语为维吾尔语非英语专业的民考汉大学生的英语教学的一些启示,也为他们的英语保持给予一些探索性思考。     

社会变迁过程中政府能力的政策学解读--基于系统论观点

中国正处于巨大的社会变迁之中，复杂性与不确定性的环境特征对政府能力提出了更高要求。从系统论的视角看，政府能力体现在政府对变迁中社会环境的反应、适应与变革能力。基于系统论的政策学解读，政府能力最终可以归为“制定”和“执行”公共政策的能力。从环境与组织管理的关系出发，围绕公共政策的生命过程，可以分别考察政府在输入、转化、输出三个环节中政策制定和政策执行的情况，进而探讨政府能力提升的路径。     

A general class of test statistics for Van Valen's Red Queen hypothesis

Van Valen's Red Queen hypothesis states that within a homogeneous taxonomic group the age is statistically independent of the rate of extinction. The case of the Red Queen hypothesis being addressed here is when the homogeneous taxonomic group is a group of similar species. Since Van Valen's work, various statistical approaches have been used to address the relationship between taxon age and the rate of extinction. We propose a general class of test statistics that can be used to test for the effect of age on the rate of extinction. These test statistics allow for a varying background rate of extinction and attempt to remove the effects of other covariates when assessing the effect of age on extinction. No model is assumed for the covariate effects. Instead we control for covariate effects by pairing or grouping together similar species. Simulations are used to compare the power of the statistics. We apply the test statistics to data on Foram extinctions and find that age has a positive effect on the rate of extinction. A derivation of the null distribution of one of the test statistics is provided in the supplementary material.     

The effect of cognitive diversity on the illusion of control bias in strategic decisions: An experimental investigation

By integrating cognitive diversity into debiasing literature, this paper contributes towards opening the black box of executive judgment. Based on information processing theory we investigate the role of cognitive diversity in strategic decision making. We apply a vignette-based experimental research design to examine the effect of cognitive diversity in teams on decision maker's illusion of control. The results of these experiments provide evidence for a positive influence of high cognitive diversity for debiasing judgment while similarly indicating no such effect for groups with low cognitive diversity. These findings suggest that group composition aspects can play an important role for improving judgment in decision making teams and open promising new avenues for studying debiasing in behavioral strategy research.     

语境理论对语篇内词汇理解的作用

词汇在英语学习中居于非常重要的地位,它对于英语水平的提高有着不可估量的作用。而语境对于理解词汇所起的作用是不容忽视的。在英语学习过程中,许多人对词汇理解的效果并不理想,主要原因就是忽略了语境在词汇理解中所起的作用。在这样的背景下,越来越多的语言学家认识到语境的重要性,尤其是语境理论对于词汇理解的指导意义和研究价值。从关联理论的角度出发,分析了语境理论对语篇中词汇理解的作用。     

Defender–Attacker Decision Tree Analysis to Combat Terrorism

We propose a methodology, called defender–attacker decision tree analysis, to evaluate defensive actions against terrorist attacks in a dynamic and hostile environment. Like most game‐theoretic formulations of this problem, we assume that the defenders act rationally by maximizing their expected utility or minimizing their expected costs. However, we do not assume that attackers maximize their expected utilities. Instead, we encode the defender's limited knowledge about the attacker's motivations and capabilities as a conditional probability distribution over the attacker's decisions. We apply this methodology to the problem of defending against possible terrorist attacks on commercial airplanes, using one of three weapons: infrared‐guided MANPADS (man‐portable air defense systems), laser‐guided MANPADS, or visually targeted RPGs (rocket propelled grenades). We also evaluate three countermeasures against these weapons: DIRCMs (directional infrared countermeasures), perimeter control around the airport, and hardening airplanes. The model includes deterrence effects, the effectiveness of the countermeasures, and the substitution of weapons and targets once a specific countermeasure is selected. It also includes a second stage of defensive decisions after an attack occurs. Key findings are: (1) due to the high cost of the countermeasures, not implementing countermeasures is the preferred defensive alternative for a large range of parameters; (2) if the probability of an attack and the associated consequences are large, a combination of DIRCMs and ground perimeter control are preferred over any single countermeasure.     

Explaining how unexploded ordnance clearance enhances livelihoods in the Lao PDR

BackgroundFollowing violent conflict, the continued presence of landmines and unexploded ordnance pose a barrier to rebuilding livelihoods. Mine action removes these explosive remnants of conflict to enable communities to safely return contaminated land to productive use. There is limited understanding, however, of how, why, in what context and in what respects mine action contributes to livelihoods. Yet, such information is required for effective resource allocation, checking underlying program assumptions, understanding benefits and potential harms.MethodsThe evaluation was undertaken in the Lao People's Democratic Republic. It used an interpretive case study design and applied the principles of realist evaluation. Program staff and local government authorities were interviewed (N = 37) and program beneficiaries. In total, 38 individual interviews with program beneficiaries were conducted and eighteen focus group interviews (9 with males, 9 with females), each with 6–9 participants.ResultsThe evaluation identified two main mechanisms through which the program ‘worked’: (1) communication pre- and post-clearance and (2) the delivery of the product (cleared land).ConclusionThe realist approach helped to refine the program theory, highlighted the role of self- and task-efficacy and community communication, assisted in identifying contextual factors that influence outcomes and suggested a revision of expected outcomes.     

Changes in the labour market and health inequalities during the years of the recent economic downturn in Italy

There is widespread concern that episodes of unemployment and unstable working conditions adversely affect health. We add to the debate by focusing on the relationship between work trajectory and the self-reported health of Italian men and women during the present economic downturn. Relying on Italian data in the EU-SILC project (from 2007 to 2010), our sample includes all individuals aged 30 to 60 in 2010, and uses multivariate binomial regression models for preliminary analyses and the Structural Equations modelling (SEM) to observe the cumulative effects of health status according to different job trajectories. Our main findings show similar pictures for men and women. Individuals who are unemployed, ejected or in precarious occupational positions have a higher risk of worsening their health status during these years.