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11.
Using a recent public expenditure dataset, this article proposes a ‘reality check’ of the level and composition of input subsidies in nine African countries between 2006 and 2013. Results show that input subsidies (1) received close to 35% of agricultural‐specific expenditure on average and (2) cover a variety of interventions, including investments in capital, such as on‐farm irrigation, and in on‐farm services, such as inspection or training. Further, the figures show that input subsidies tended to become entrenched in agricultural budgets over time, leading to sub‐optimal execution rates, and were primarily funded by the national taxpayer, while donors invested more in public goods. Findings confirm that input subsidies crowded out other spending categories likely to be more supportive of long‐term agricultural development objectives. The article concludes that the political economy of input subsidies should be directed to making more concrete efforts to attain a better balance of public expenditure on agriculture. Furthermore, policy‐makers should aim to increase the efficiency and policy coherence of input subsidies, since merely abolishing them is likely to be unfeasible in the short term.  相似文献   
12.
文章介绍了中国科普投入产出的基本现状,结合中国科普工作的实际情况,构建了中国科普投入产出评价指标体系初步框架.应用数据包络分析法(DEA),选取了中国科普统计2006-2013年间的数据,分析评价了中国科普投入产出效率,得到效率有待提高的初步研究结论.  相似文献   
13.
以英语方式副词位置为强化对象,研究输入流、文本强化以及两者结合使用这三种输入强化方式是否能够帮助学习者习得英语方式副词的位置规则,并对其效果进一步深入探讨。实验结果表明:三种输入强化方式都能帮助学生习得方式副词位置规则,但输入强化的有效应用是有条件的,输入强化的效果会受研究中受试者以及被强化的对象等因素的影响。此外,相对于单一强化,复合强化通常更能有效地促进目标语的学习,但当单一强化能有效地促进目标语学习的时候,复合强化不能帮助学习者取得显著性的优异成绩,从而表明复合强化并不总是必要的。  相似文献   
14.
探讨了输入模态对学生认知负荷和听力理解的影响。90名来自两个平行班的大学英语学生被平均分为三个小组参加实验:文本输入组,声音输入组,文本和声音输入组。文本组的听力题目用文本呈现,声音组的听力题目仅用声音呈现,文本和声音组的题目则是采用文本和声音双重模态呈现。认知负荷量表结果和听力测试结果显示不同模态的听力输入形式对听力成绩有显著影响:文本组学生的成绩最高,其次是文本加音频组,音频输入组的成绩最低。认知负荷量表结果显示文本组的认知负荷最低,然后是文本加音频组,音频输入组的认知负荷最高。认知负荷与听力成绩的相关分析显示负荷程度与听力成绩呈负相关。研究结果对听力教学有较好的借鉴作用。  相似文献   
15.
Christoph Gietl 《Statistics》2017,51(3):668-684
This paper proves continuity of f-projections and the continuous dependence of the limit matrix of the iterative proportional fitting procedure (IPF procedure) on the given matrix as well as the given marginals under certain regularity constraints. For finite spaces, the concept of f-projections of finite measures on a compact and convex set is introduced and continuity of f-projections is proven. This result is applied to the IPF procedure. Given a nonnegative matrix as well as row and column marginals the IPF procedure generates a sequence of matrices, called the IPF sequence, by alternately fitting rows and columns to match their respective marginals. The procedure is equivalent to cyclic f-projections. If the IPF sequence converges, the application of the continuity of f-projections yields the continuous dependence of the limit matrix on the given matrix. By generalized convex programming and under some constraints, it is shown that the limit matrix of the IPF sequence continuously depends not only on the given matrix but also on the marginals.  相似文献   
16.
In performance evaluations, data without explicit inputs (such as index data, pure output data) are widely used. To directly use such data, this paper presents a study on building DEA models without explicit inputs, so-called DEA-WEI models, which are applicable to the evaluation applications where inputs are not directly considered. We provide an axiom foundation of these kinds of models, and further discuss how to incorporate value judgments of decision makers into these DEA-WEI models. Several such models are derived. Finally, applications of the DEA-WEI models are presented.  相似文献   
17.
斜井冻结技术尚处于摸索研究阶段,国内无统一的施工规范。在李家坝煤矿斜井冻结工程实践的基础上开展应用性研究,详细阐述了斜井局部冻结的设计原则、施工关键技术,尤其是快速造孔施工及冻结管保温层施工工艺,提出了冻结管保温接头处理方式,成功应用了斜井冻结步进式投入法,解决了斜井局部冻结关键技术,为类似局部冻结工程提供了借鉴和参考。  相似文献   
18.
联结主义理论给英语教学新的启示。本文在理论分析的基础上,结合英语阅读教学的现状和个人教学实践,提出了阅读教学中应用联结主义的教学步骤。探讨了强化注意程度,激活输入的语言信息,提高输出意识的教学方法。  相似文献   
19.
Interdependency analysis in the context of this article is a process of assessing and managing risks inherent in a system of interconnected entities (e.g., infrastructures or industry sectors). Invoking the principles of input-output (I-O) and decomposition analysis, the article offers a framework for describing how terrorism-induced perturbations can propagate due to interconnectedness. Data published by the Bureau of Economic Analysis Division of the U.S. Department of Commerce is utilized to present applications to serve as test beds for the proposed framework. Specifically, a case study estimating the economic impact of airline demand perturbations to national-level U.S. sectors is made possible using I-O matrices. A ranking of the affected sectors according to their vulnerability to perturbations originating from a primary sector (e.g., air transportation) can serve as important input to risk management. For example, limited resources can be prioritized for the "top-n" sectors that are perceived to suffer the greatest economic losses due to terrorism. In addition, regional decomposition via location quotients enables the analysis of local-level terrorism events. The Regional I-O Multiplier System II (RIMS II) Division of the U.S. Department of Commerce is the agency responsible for releasing the regional multipliers for various geographical resolutions (economic areas, states, and counties). A regional-level case study demonstrates a process of estimating the economic impact of transportation-related scenarios on industry sectors within Economic Area 010 (the New York metropolitan region and vicinities).  相似文献   
20.
本文针对广告业长期存在的五个"思想问题"进行了分析,提出了广告业要重视练内功,要改善知识结构,要拓宽服务领域,提高广告经营水平,要改变短期行为等多种观点。认为广告业如果不能真正解决自身的问题,就无法应对国际广告资本的挑战。  相似文献   
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