教育时空拓展:教师专业成长的机遇与挑战

随着人类文明的进步、社会的发展以及信息技术的普及，教育时间和空间得到迅速拓展。教育时空拓展正如一把双刃剑，给教育活动的实施带来机遇的同时也带来了挑战。教师作为教育活动的主要组织者和实施者，在享受机遇的同时也要迎接教育时空拓展所带来的挑战。通过分析教育时空拓展的内涵与表征，发现教师专业成长正处在社会化、终身化与数字化的发展大潮中，因此教师要充分利用好教育时空拓展带来的机遇，同时慎重应对由此面临的挑战，不断提高应变能力，以促进教师专业成长和教育事业的发展。     

城镇化、工业化对农业全要素生产率增长的影响研究——来自重庆37个县(区)面板数据的证据

文章基于2000—2016年重庆37个县（区）面板数据，使用序列DEA方法测算了重庆农业全要素生产率变动，在此基础上探讨了重庆农业全要素生产率增长的时间演变，并从理论和实证层面系统考察了城镇化和工业化对农业全要素生产率增长的影响。结果表明：首先，2000—2016年间重庆市农业全要素生产率呈上升趋势，2007年后重庆市农业全要素生产率增长更为明显，并且重庆市各地区呈现出明显的空间不平衡性。其次，动态面板模型的实证结果表明城镇化对农业全要素生产率增长具有显著正向影响，工业化对农业全要素生产率增长也具有显著正向影响。最后，研究还发现基础设施、教育水平以及金融发展程度对农业全要素生产率增长均具有显著正向影响，而产业结构对农业全要素生产率增长具有显著负向影响。     

Presence Through Absence: Phylloxera and the Viticultural Imagination in McLaren Vale,South Australia

Grape phylloxera is an insect pest that has destroyed vineyards and brought ruin to winegrowing regions worldwide. In South Australia, however, strong biosecurity regulations have ensured it has remained absent. In this absence phylloxera takes on powerful symbolic value, and regional viticultural identities may be imagined in relation to the presence of phylloxera elsewhere. This paper draws from ethnographic research with grape growers and wine producers in McLaren Vale, a region whose vineyards are understood through this ‘phylloxera-free’ paradigm. The article specifically explores controversies around modification of South Australian biosecurity regulations in a way that favoured large winegrowing corporations’ need to more easily move material between regions, to the perceived detriment of vineyard security. The phylloxera risk has economic, social and symbolic dimensions in McLaren Vale, where the insect has become symbolically aligned with the most impersonal, pervasive and destructive aspects of globalised wine capitalism.     

Availability analysis for general repairable systems with repair time threshold

Availability analysis is an important issue in many practical fields. This paper investigates the availability for general repairable systems with repair time threshold. Based on practical applications, a repair time threshold is introduced. If the period of a repair is less than a predefined time threshold, then the system may be considered as working during this period, i.e., the effect of the repair could be neglected. Otherwise, if the period of a repair is longer than the given threshold, then the system is considered as working from the beginning of the system failure until the repair time exceeding the threshold, i.e., the time point of the system down could be delayed. We consider both constant and random repair time threshold. This paper valuates the user-perceived availability, when the user does not experience any service interruption because the duration of repair is too short. The results can be applied in reliability engineering, queueing theory and many other fields. A numerical example for ventilator system is presented to demonstrate the application of the developed approach.     

Oracle GMM estimation for misspecified models via thresholding

We propose a thresholding generalized method of moments (GMM) estimator for misspecified time series moment condition models. This estimator has the following oracle property: its asymptotic behavior is the same as of any efficient GMM estimator obtained under the a priori information that the true model were known. We propose data adaptive selection methods for thresholding parameter using multiple testing procedures. We determine the limiting null distributions of classical parameter tests and show the consistency of the corresponding block-bootstrap tests used in conjunction with thresholding GMM inference. We present the results of a simulation study for a misspecified instrumental variable regression model and for a vector autoregressive model with measurement error. We illustrate an application of the proposed methodology to data analysis of a real-world dataset.     

论近代川边治理与国防安全：从赵尔丰到刘文辉

风云激荡的近代“川边”，历任主政者的川边治理成效殊异：赵尔丰籍“平康三策”，锐意进取，开拓出广阔的川边境域，成功践行“固川保藏”方略。尹昌衡藉个人英雄主义维持短暂的绚烂；其后走马灯式的镇守使无法掌控川边局势，失地溃败；颇具政治韬略的刘文辉，妥善处理民族关系，稳固川边，促使西康成功建省。34年的川边治理为现代西南边疆治理留下了鲜活的经验教训，川滇藏结合部需要新的边疆治理统筹。     

Translating cross-lagged effects into incidence rates and risk ratios: The case of psychosocial safety climate and depression

Longitudinal studies are the gold standard of empirical work and stress research whenever experiments are not plausible. Frequently, scales are used to assess risk factors and their consequences, and cross-lagged effects are estimated to determine possible risks. Methods to translate cross-lagged effects into risk ratios to facilitate risk assessment do not yet exist, which creates a divide between psychological and epidemiological work stress research. The aim of the present paper is to demonstrate how cross-lagged effects can be used to assess the risk ratio of different levels of psychosocial safety climate (PSC) in organisations, an important psychosocial risk for the development of depression. We used available longitudinal evidence from the Australian Workplace Barometer (N?=?1905) to estimate cross-lagged effects of PSC on depression. We applied continuous time modelling to obtain time-scalable cross effects. These were further investigated in a 4-year Monte Carlo simulation, which translated them into 4-year incident rates. Incident rates were determined by relying on clinically relevant 2-year periods of depression. We suggest a critical value of PSC?=?26 (corresponding to ?1.4 SD), which is indicative of more than 100% increased incidents of persistent depressive disorder in 4-year periods compared to average levels of PSC across 4 years.     

基于股价预测的泛证券投资组合策略

本文基于期望效用最大化和L₁-中位数估计研究了在线投资组合选择问题。与EG（Exponential Gradient）策略仅利用单期价格信息估计价格趋势不同，本文将利用多期价格信息估计价格趋势，以提高在线策略的性能。首先，基于多期价格数据，利用L₁-中位数估计得到预期价格趋势。然后，通过期望效用最大化，提出一个新的具有线型时间复杂度的在线策略，EGLM（Exponential Gradient via L₁-Median）。并通过相对熵函数定义资产权重向量的距离，进而证明了EGLM策略具有泛证券投资组合性质。最后，利用国内外6个证券市场的历史数据进行实证分析，结果表明相较于UP（Universal Portfolio）策略和EG策略，EGLM策略有更好的竞争性能。     

多渠道医疗门诊挂号的时间策略研究

现阶段多种门诊挂号方式并存时，根据患者特性制定不同的等待时间策略尤为重要。本文考虑门诊挂号的三种渠道：直接排队挂号渠道、电话预约挂号渠道与O2O预约挂号渠道。在价格外生前提下，综合考虑患者的渠道偏好程度、时间敏感性与提前支付敏感性，基于效用理论构建患者的渠道选择模型。根据该模型推导得出不同市场条件下医院的需求，医院再据此制定患者的等待时间策略以达到利润最大化的目的。研究发现：当医院仅开通单一挂号渠道时，若患者的时间敏感度越大、渠道偏好程度越小，等待时间均越小；开通某两种挂号渠道时，还需考虑患者对两种渠道的偏好比例，偏好某种渠道的患者比例增加，选择该渠道的患者等待时间增加，选择另一渠道的患者等待时间减小；同时开通三种渠道时，最偏好某渠道的患者比例越大，选择该渠道的患者的等待时间也越大；在所有情况下，患者对提前支付的敏感度均不影响最优等待时间的制定。     

A discrete-time risk model with Poisson ARCH claim-number process

Abstract

In this paper, we propose a discrete-time risk model with the claim number following an integer-valued autoregressive conditional heteroscedasticity (ARCH) process with Poisson deviates. In this model, the current claim number depends on the previous observations. Within this framework, the equation for finding the adjustment coefficient is derived. Numerical studies are also carried out to examine the impact of the Poisson ARCH dependence structure on the ruin probability.