“显性学习”与“隐性学习”的博弈留给我们的启示

＂显性学习＂和＂隐性学习＂有着不同的功能和效果。在语言教学实践中,怎样安排利用显性学习和隐性学习才是最合理的？不同的理论模式对此有不同的解读,导致显性学习与隐性学习发生了一系列＂太极推搡＂般的博弈。博弈的结果是,＂精讲多练＂原则应运而生。这似乎是一个合理的归宿。这场博弈的背后包含着丰富的语言学原理,给二语教学留下了有益的启示。     

Optimal block designs comparing treatments with a control when the errors are correlated

The efficient design of experiments for comparing a control with v new treatments when the data are dependent is investigated. We concentrate on generalized least-squares estimation for a known covariance structure. We consider block sizes k equal to 3 or 4 and approximate designs. This method may lead to exact optimal designs for some v, b, k, but usually will only indicate the structure of an efficient design for any particular v, b, k, and yield an efficiency bound, usually unattainable. The bound and the structure can then be used to investigate efficient finite designs.     

A novel portfolio selection model in a hybrid uncertain environment

The future returns of each securities cannot be correctly reflected by the securities data in the past, therefore the statistical techniques and the experts’ judgement and experience are combined together to estimate the security returns in the future. In this paper, the returns of each securities are assumed to be fuzzy random variables, then following the ideas of mean variance model a new portfolio selection model in a hybrid uncertain environment is proposed. Moreover, the λ-mean variance efficient frontiers and λ-mean variance efficient portfolios are defined, and the properties of λ-mean variance efficient portfolios located on different λ-mean variance efficient frontiers are discussed. Finally, a numerical example is presented to illustrate the proposed portfolio selection model. On the basis of the results, we can conclude that the proposed model can provide the more flexible results.     

Portfolio rebalancing with an investment horizon and transaction costs

In this paper we consider the problem of rebalancing an existing financial portfolio, where transaction costs have to be paid if we change the amount held of any asset. These transaction costs can be fixed (so paid irrespective of the amount traded provided a trade occurs) and/or variable (related to the amount traded). We indicate the importance of the investment horizon when rebalancing such a portfolio and illustrate the nature of the efficient frontier that results when we have transaction costs. We model the problem as a mixed-integer quadratic programme with an explicit constraint on the amount that can be paid in transaction cost. Our model incorporates the interplay between optimal portfolio allocation, transaction costs and investment horizon. We indicate how to extend our model to include cardinality constraints and present a number of enhancements to the model to improve computational performance. Results are presented for the solution of publicly available test problems involving up to 1317 assets.     

论清初《诗品》接受史的“异质性”--以陈祚明对潘岳、陆机、陶渊明的批评为中心

清初诗论家陈祚明对《诗品》的批评存在鲜明的异质性。陈祚明反对钟嵘“陆才如海,潘才如江”的说法,认为钟嵘对陶渊明品第不当,对诗旨阐发不足。他认为潘胜于陆,陶诗可与杜诗并驾齐驱,陶诗亦有入世之意,不宜专以隐逸述陶诗之旨。钟嵘之所以强调传统,否定新变,是为了反对以沈约为首的声律论;陈祚明之所以主张溯唐诗之源,提倡“情为辞先”的诗学观,是为了折中调和明前后七子和竟陵派之弊。不同的诗学语境、批评目的,导致了“异质性”的产生。     

构建解决拖欠农民工工资问题的长效机制

解决农民工工资拖欠问题,应从完善维护农民工权益的法律体系、建立城乡统一的劳动力市场、提高农民工的组织化程度、建立农民工工资保障金制度、建立企业的信用档案和发挥媒体的舆论监督作用等方面入手,构建解决拖欠农民工工资问题的长效机制。     

证券技术分析何以预测

证券技术分析自诞生以来,其合理性和有效性就一直受到了普遍的关注.有些人认为技术分析的作用非常有限,甚至是毫无根据和无效的.这一种观念在有效市场假说创立以来更上升到了理论的高度.本文认为,技术分析作为一种在证券投资中被广泛应用的预测股价变动的工具,具有一定的内在合理性因素,可以用来对股价变动的趋势作出预言.但必须指出:技术分析的科学性尚不能得到承认.     

无风险利率下投资组合的有效前沿

本文考虑无风险利率下投资组合的有效前沿问题。本文首先把Markowitz模型的有效前沿用投资组合的权重向量表示出来, 然后将无风险利率下投资组合的有效前沿也用投资组合的权重向量表示出来, 再由无风险利率下投资组合有效前沿的定义即可求出这个有效前沿。     

‘A Direct Act of Resurgence,a Direct Act of Sovereignty’: Reflections on Idle No More,Indigenous Activism,and Canadian Settler Colonialism

Abstract

In the winter of 2012, the Canadian political scene was shaken by the emergence of ‘Idle No More', a collection of protests directed by and largely comprised of Indigenous peoples. Originally, a response to a variety of legislation that was being passed through the Canadian government at the time, Idle No More spread across the country and around the world. In this paper, I argue that, drawing from Indigenous nationhood movements that extend back through five centuries, Idle No More represents a renewed assertion of Indigenous sovereignty in opposition to settler colonisation. Through transgressive actions, Idle No More has brought online activism into alignment with embodied defences of land and place, challenging Canadian sovereignty and Settler identity in multiple and creative ways. However, settler colonial tendencies in Canadian politics have sought to reinscribe Idle No More within established, generic political binaries. This paper positions Idle No More as a ‘movement moment’ that reveals significant insights about Indigenous activism, conservative politics, leftist resistance, and persistent settler colonialism in Canada.