Residual analysis for spatial point processes (with discussion)

Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.     

Fair Trade Certification: The Case of Tea Plantation Workers in India

This article analyses the impact of Fair Trade certification by focusing on its interactions with the patron–client relations traditionally established between management and workers in tea plantations in India. It argues that the invisibility of Fair Trade among workers, which generally reinforces existing patron–client relations through Fair Trade premiums, inversely hides the patronage of the management, and that workers are empowered when a premium is invested in a community development project led by an independent third‐party organisation.     

资产专用性对确权后农地流转的影响

农地确权后,农户对农地转出多持中立或否定的态度,这与产权明晰促进交易的产权理论大相径庭。文章探讨了资产专用性对确权后农地流转的作用机理,并运用吉林省9市1444个农户数据对其进行实证分析。结果表明：农地确权后,土地资产、农业资产、地理位置以及人力资本等专用性抑制农户转出农地,农业资产和人力资本专用性抑制农户提高农地租金,而社会资本专用性则分别存在促进作用;农业资产、地理位置以及人力资本等专用性抑制农户更长时间转出农地;农业资产专用性对转出农地须要签订合约具有抑制作用,而地理位置专用性则存在促进作用。     

对新版《李大钊全集》第二卷有关日本问题的疏证与补注

《李大钊全集》＂最新注释本＂第2卷,对李大钊著作中提及的与日本有关的问题,有的注为＂不详＂;有的虽未注＂不详＂,也是应该予以注释的。在已作注释的一些问题中,也有值得商榷之处。     

关于标点符号使用情况的调查及思考

针对大学生对标点符号的实际运用现状展开调查,发现存在的主要问题包括：对标点符号的运用不予重视而随意圈点,忽视句子结构关系而瞻前忘后,不明句意和用法而张冠李戴。这不仅影响到大学生的阅读理解和思想表达,而且也给社会语文生活带来负面影响。由此提出应当采取多种措施来巩固和提高大学生的语言文字素质。     

Union organizing effort and success in the U.S., 1948–2004

While union density in the public sector has increased in recent decades, private sector union density in the U.S. has declined steadily since the mid-1950s. Scholars have evoked a variety of explanations to account for the decline in union membership, but substantially less attention has been devoted to understanding the contribution of the union organizing process as governed by the National Labor Relations Board (NLRB). In this paper, we focus on two aspects of this process: union organizing effort (the effort to establish union representation elections to organize non-unionized workers) and union organizing success (success in winning union representation elections). Using annual time series data for the U.S. from 1948 to 2004, we show that there has been a long-term decline in both union organizing effort and union organizing success, which likely contributes to declining union density. We focus on three explanations for these changes: the political–legal environment for unions, deindustrialization and globalization, and employer opposition to unionization efforts. We find that each of these factors contributes to organizing effort and success and conclude with a discussion of the implications of this research for future mobilization efforts.     

无线移动自组网混合式密钥管理方案研究

基于门限机制的密钥管理方案能提供高的安全性,但认证成功率较低,可扩展性差;基于证书链的密钥管理方案适合自组网的特点,但其安全性仅取决于证书链中节点的信任度,不能满足高安全要求的应用环境。该文提出了门限机制和证书链信任值方法相结合的混合式密钥管理和认证方案,在增加少量通信量的情况下,方案提高了自组网的认证成功率和系统的安全性,较好地平衡了自组网的安全性和认证成功率,满足自组网应用的安全要求。     

江苏茶农选择有机种植方式的影响因素分析

有机种植方式影响有机产品的产量、价格和成本,同时生产者必须每年进行有机认证,而认证的费用是一笔固定的支出。如何使生产者自愿参加认证,从最基本的经济学角度分析,只要价格、产量和成本变动所带来的收益能够弥补由于认证所带来的固定费用的支出,那么生产者就有可能选择有机种植方式,参加有机认证。产量、成本和收益都是种植规模的函数,可以推论,生产者是否选择有机种植方式、参加有机认证,其种植规模的大小是一个重要的原因。本文从规模入手,试图寻找一个“门槛面积”,认为达到或超过该面积的生产者就有可能自愿采用有机种植方式。     

农产品生产主体质量安全多重认证行为研究

叠加认证能显著提升消费者对食品质量安全的信任程度和额外支付意愿。采用专业大户、合作社和龙头企业三类现代农业生产经营主体的数据,利用Heckman两阶段选择模型分析浙江省食用农产品生产主体的质量安全多重认证行为后发现,生产主体的多重认证行为除受生产主体的经营规模、人力资本、自有品牌状况等个体特征与市场结构特征显著影响外,还受到市场激励、主体责任压力和交易成本的显著影响。总体而言,生产主体的质量安全认证行为是在自身能力及环境约束下的成本收益权衡,生产主体的质量安全多重认证行为更主要是受市场激励和主体内在责任的驱动,而非政府的规制压力。     

试论北宋慢词的演变轨迹

北宋的慢词创作经历了一个不断典雅化的过程。柳永、秦观、周邦彦是北宋慢词发展进程中的三位有代表性的作家,他们的词作分别体现了慢词从初创到走向典雅这一进程中的不同特征。通过对他们作品中表现出来的感情内涵、表现手法布局结构、语言特点等方面的比较分析,可以看出慢词在北宋的演变轨迹。