Modelling Variability in the Branching Structure of Strawberry Inflorescences

The branching structure of inflorescences of the cultivated strawberry ( Fragaria × ananassa Duch.) is very variable. This paper demonstrates that some aspects of this variability are well described by a simple stochastic model of branching that has two adjustable parameters. The model is shown to provide a good fit to data from a set of almost 700 inflorescences of the cultivar Elsanta, collected over two successive years. For one parameter the maximum likelihood estimator is a moment estimator which is fully efficient even if the detailed branching structure of the inflorescences is not recorded. This parameter provides a convenient summary of branching vigour. The maximum likelihood estimator of the second parameter must be determined iteratively and can be quite inefficient unless the full branching structure is recorded. The model demonstrates that branching structure is affected by the order in which inflorescences emerge on the plant.     

e‐Integration in the Supply Chain: Barriers and Performance*

Current opinion holds that Internet‐based supply chain integration with upstream suppliers and downstream customers (called “e‐integration” in this paper) is superior to traditional ways of doing business. This proposition remains untested, however, and similarly we know little about what are the upstream, internal, and downstream barriers to implementing e‐integration. This paper empirically addressed these questions using data from a large single nation study, and found (1) a positive link between e‐integration and performance, and (2) that internal barriers impeded e‐integration more than either upstream supplier barriers or downstream customer barriers. Findings from this study contribute to our theoretical understanding of implementing change in contemporary supply chains, and have important implications for manufacturers interested in improving their supply chain's performance using the Internet.     

Francine Blau receives IZA Prize in Labor Economics

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Francine Blau receives IZA Prize in Labor Economics     

The Role of Organizational and Information Technology Antecedents in Reengineering Initiation Behavior*

Business Process Reengineering (BPR) has been a major catalyst of the pervasive organizational change we have witnessed over the past decade. Although one can speculate on the reasons for the popularity of this phenomenon, it is important that we carefully examine its underlying antecedents for initiation, implementation, and ultimately success, if we are to add value to practitioners of this concept. This study empirically examines the importance of facets of the organizational structure, IT knowledge resources and infrastructure, and the IS function in the initiation of BPR. Data from 313 corporations were gathered using a carefully validated survey, and initiators were compared with noninitiators. The results strongly suggest that client-server architectures, the strategic integration of IS, and cross departmental interaction are among the more important factors facilitating initiation and can be important inputs in a BPR decision-making process. The study attempts to build a contingent theory for BPR, and the more sustainable notion of fundamental process change.     

社会工作质性评估研究的回顾(1990-2003)对中国社会工作的启示

在社会科学的历史中,定量和定性研究的争论持续了差不多半个世纪。随着研究者对实证主义的质疑,质性研究的数目逐渐增加。根据布瑞曼(Bryman,1988)的看法,质性研究有以下特点:(1)透过被访者的眼睛看世界;(2)描述日常生活情境的细节;(3)了解在不同社会范畴的背景中的行为及意义;(4)强调过程;(5)倾向采用文字及结构灵活的研究设计;(6)尽量避免在研究初期确立理论和观念。邓泽和林肯(Denzin & Lincoln,1998)也指出,质性研究有以下元素:(1)采用多元的研究手法;(2)涉及自然和诠译的角度;(3)在自然的情况下作出研究;(4)尝试理解和分析不同现象的…     

Substance use and other factors associated with child welfare case duration: Looking beyond out of home care

Little is known about factors associated with child welfare case duration. Understanding factors associated with case duration may help stakeholders make more informed decisions about funding and service allocation and improve compliance with federal law. This study had two research questions: (1) What factors are associated with child welfare case duration? And (2) Do factors differ depending on whether children were placed exclusively with parents or with others (e.g. relatives and foster care) during the case? The study sample consisted of families (N = 874) with co-occurring child maltreatment and substance use in one midwestern state in the United States between 2007 and 2016. Linear regression models were used to identify correlates of case duration while controlling for child placement status. Overall, having a child under 1 year of age, benzodiazepine use, methamphetamine use and injection drug use were all associated with longer case duration, whereas marijuana use with no other substance use was associated with shorter case duration. Additionally, factors associated with case duration differed based on child placement status during the case. These findings suggest important heterogeneity in families involved with child welfare services and may allow for proactive mitigation of cases at greater risk.     

Responding to joint attention as a developmental catalyst: Longitudinal associations with language and social responsiveness

Joint attention (JA), infants' ability to engage in triadic attention with another person and a separate object or event, emerges in infancy. Responding to joint attention (RJA) develops earlier than initiating joint attention (IJA) and may benefit from a reconceptualization from a competence to a skill that varies in performance. Investigating associations between RJA performance and important skills of toddlerhood such as language, social responsiveness, and executive function (EF) in typically developing samples can better elucidate how RJA may serve as a developmental precursor to later dimensional skills, with implications for both typical and atypical development. Here, 210 (82% White) infants completed the Dimensional Joint Attention Assessment (DJAA), a naturalistic play-based assessment of RJA, at 8–15 months. At 16–38 months social responsiveness, verbal ability, and EF were assessed. Multilevel models showed that DJAA scores were associated with later verbal abilities and parent-reported social responsiveness. Exploratory analyses showed trend-level associations between RJA and EF. Results establish the content validity of the DJAA as a measure of RJA, and longitudinal associations with later verbal ability and social responsiveness. Future work should examine EF emergence and consolidation, and RJA and later EF associations.     

Stakeholder Green Pressure and New Product Performance in Emerging Countries: A Cross-country Study

Despite the burgeoning literature on stakeholder green pressure, research is scarce on how it influences eco-product innovation and new product performance. This article examines stakeholder green pressures as antecedents of eco-product innovation and new product performance in firms operating in resource-constrained countries. Using data gathered from surveys in Vietnam (N = 183) and Ghana (N = 217), we find that the positive effects of stakeholder green pressures on new product performance are serially mediated by environmental sustainability orientation and eco-product innovation. Our findings contribute to ongoing efforts to clarify the mechanisms channelling stakeholder pressures into new product performance in resource-constrained environments.     

Social intelligence as moderator in the relation between narcissism and aggression in at-risk adolescents

This study examined the moderating role of social intelligence (SI) in the associations of grandiose and vulnerable narcissism (VN) with peer-reported overt and relational aggression (RA). The sample consisted of 286 adolescents aged 15 to 19 recruited from a residential program for youth who have dropped out of school. Results showed that whereas grandiose narcissism (GN) was related to both forms of aggression, VN was related to neither overt nor RA. However, SI moderated the relation between VN and both forms of aggression such that SI works as either a risk or protective factor for adolescents with higher levels of narcissism depending on the subdimensions of SI and aggression. The findings indicate that SI may play a role in how adolescent peers perceive the behavior of relatively narcissistic individuals.