电商参与会促进农户农产品质量认证吗?——基于黄土高原苹果优势产区农户的分析

作为数字经济新业态的农产品电子商务成为促进农业高质量发展的有效途径。基于黄土高原苹果优势产区农户实地调研数据,使用多维固定效应模型分析电商参与对农户农产品质量认证的影响;利用中介效应模型和KHB方法剖析电商参与促进农户农产品质量认证的作用机制。研究结果表明:电商参与能够显著提升农户农产品质量认证的概率,同时增加了多重质量认证的可能;参与电商通过提高农户农产品质量认证意愿、增加农产品市场信息以及促进农产品品牌建设三个途径影响农产品质量认证。在此基础上,提出应加强农村信息基础设施建设与电商技术培训,提高农产品质量认证和品牌推广等对策,以此促进农户进行农产品质量认证,实现农业高质量发展。     

试论时间价值观

时间是一种重要的资源。时间价值观是个体以自身的需要为尺度对时间重要性的稳定态度和观念。时间价值观含有时间资源观、时间效率观、时机观、时间顺序观等方面的意义。时间价值观的结构可以有不同的划分。时间价值观受社会文化传统、个体的年龄因素、个体性格、社会环境等因素的影响。心理学对时间价值观的研究在理论上和应用中都有着重要的意义     

Estimating a sensitive proportion through randomized response procedures based on auxiliary information

Randomized response techniques are widely employed in surveys dealing with sensitive questions to ensure interviewee anonymity and reduce nonrespondents rates and biased responses. Since Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, many ingenious devices have been suggested to increase respondent’s privacy protection and to better estimate the proportion of people, π _A , bearing a sensitive attribute. In spite of the massive use of auxiliary information in the estimation of non-sensitive parameters, very few attempts have been made to improve randomization strategy performance when auxiliary variables are available. Moving from Zaizai’s (Model Assist Stat Appl 1:125–130, 2006) recent work, in this paper we provide a class of estimators for π _A , for a generic randomization scheme, when the mean of a supplementary non-sensitive variable is known. The minimum attainable variance bound of the class is obtained and the best estimator is also identified. We prove that the best estimator acts as a regression-type estimator which is at least as efficient as the corresponding estimator evaluated without allowing for the auxiliary variable. The general results are then applied to Warner and Simmons’ model.     

Nonparametric control charts based on runs and Wilcoxon-type rank-sum statistics

In this article, we introduce three new distribution-free Shewhart-type control charts that exploit run and Wilcoxon-type rank-sum statistics to detect possible shifts of a monitored process. Exact formulae for the alarm rate, the run length distribution, and the average run length (ARL) are all derived. A key advantage of these charts is that, due to their nonparametric nature, the false alarm rate (FAR) and in-control run length distribution is the same for all continuous process distributions. Tables are provided for the implementation of the charts for some typical FAR values. Furthermore, a numerical study carried out reveals that the new charts are quite flexible and efficient in detecting shifts to Lehmann-type out-of-control situations.     

Participatory shaping of community futures in e‐waste processing hubs: Complexity,conflict and stewarded convergence in a Palestinian context

This article describes an unconventional participatory development approach carried out in an informal e‐waste hub in South‐West Hebron, an area that has collected and processed the bulk of Israeli e‐waste for over a decade. Our approach contributes to the critique and recovery of community representation in participatory development and the search for ways to facilitate representative community engagement. Specifically, we describe our use of a novel Delphi‐like method that allowed us to facilitate a broadly endorsed development trajectory within a heterogeneous and conflicted community. We show how the results yielded by this approach diverged from those that were likely to emerge from more facile forms of participation in ways that are important for other similar e‐waste hubs internationally, which face a destructive status quo on the one hand, or the economically ruinous international policies that ban e‐waste trade from “developed” to “developing” countries on the other. Despite real tensions and cleavages within the affected communities, the process described facilitated a shift from deadlocked environmental versus livelihood positions towards building capacity and regulating existing informal e‐waste trades to preserve livelihoods dependent on these.     

Class participation as a pedagogical tool in social work education

Class participation is an essential part of the social work pedagogy. However, active student engagement in classes is inconsistent and varies based on factors such as social backgrounds, educational background, and individual characteristics. Instructors often evaluate participation based on frequency of verbal contributions. Evaluation criteria are often unarticulated or difficult to measure, presenting numerous challenges for instructors and students alike. A model of reflective self-assessment of participation by students, paired with timely instructor feedback is put forth in this paper to mitigate these concerns. The steps in this model include initial self-assessment, goal setting, midterm review, and a final review. The process of continuous self-evaluation and problem-solving is discussed as strategies that aid the process of class participation. Three instructor touch points are suggested: at the goal-setting stage, the midterm review, and the final grade. Throughout the paper, connections to social work practice and social work pedagogy are highlighted. This model has yet to be implemented in a social work school’s curriculum. Challenges in the implementation and resolution of those challenges are also presented. This model suggests ways to enhance opportunities for student engagement and integration into graduate programs, in addition to fostering valuable skills for future practice in the field.     

Ségrégation professionnelle selon la durée du travail en Europe

L'auteur évalue la ségrégation professionnelle selon la durée du travail dans quinze pays européens, à partir de données de l'Enquěte européenne sur les forces de travail. Il recherche les déterminants de cette ségrégation par une analyse de régression reposant sur trois groupes d'indicateurs (quantité d'emploi, qualité de l'emploi et institutions). De façon générale, la ségrégation observée est plus forte chez les hommes que chez les femmes, et chez les jeunes que chez les adultes. Elle est plutôt corrélée avec la quantité d'emploi chez les hommes, alors que des variables des trois groupes d'indicateurs interviennent chez les jeunes et les femmes adultes.     

Why does class matter? Policy attitudes,mechanisms, and the case of the Nordic countries

In most democracies, classes tend to vary with respect to an array of attitudes and behaviours, and differences are large within a number of European polities. What mechanisms lie behind these differences? Do they relate primarily to individuals’ material interests, as assumed by traditional class theories, or instead, to socialization and self-selection factors? This paper seeks to extend theory and research through an analysis of mechanisms behind class differences in policy attitudes. Our focus is on the Nordic countries, where class differences are extensive and well-documented in past scholarship. We take advantage of high-quality European Social Survey data for Denmark, Finland, Norway, and Sweden. Analyzing three policy arenas and the 9-category European Socio-economic Classification scheme (ESeC), we find evidence that class-related factors help to explain cleavages in attitudes. Comparisons with the more detailed, 103-category International Standard Classification of Occupation scheme (ISCO) suggest that these factors explain less “micro-class” occupational variation. Results shed new light on mechanisms behind class differences, and the empirical foundations of established class theories. These and other implications are discussed in the conclusion.     

Crying for Food: The Mexican Myths of ‘La Llorona’ and ‘The Hungry Woman’ in Cherríe L. Moraga

The Mexican legend of ‘La Llorona’ (‘The Weeping Woman’), who drowned her children out of revenge for being abandoned by her lover, and the Aztec creation myth of ‘The Hungry Woman’ — crying constantly for food, with mouths all around her body — have inspired Chicana writers in the symbolic representation of their own yearning, be it sexual, identity-building, or anti-patriarchal. This essay seeks to lay the mythical groundwork within this topic, as well as to illustrate with some particular examples the different reappropriations of these myths in Cherríe L. Moraga, mainly in her play The Hungry Woman: A Mexican Medea (2001). With a view to opening up a past ‘that can provide a kind of road map to our future’ (: ix), these examples of transgressive women will be deprived of the feminine colonial passivity imbued by the dominant male discourse, and analysed as a complex, active, polyvalent mythological female corpus that integrates both life and death, womb and grave. This hybrid approach is inherent to the Aztec mythology on which Moraga relies in order to transcend Manichaeistic resolutions and probe the social, political, and gender reasons leading a hungry mother to commit infanticide.