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1.
In theory, learning from past mistakes should result in adapted and improved development policy. However policy learning can be difficult to achieve, and the link between learning and policy change is neither direct nor immediate. In this study we look at learning in agro-industrial policy in Ghana, by tracing the interest in sugar production and tomato processing over six decades. Specifically we ask why four failed factories established in the early 1960s have continued to play central roles in both policy and public discourse. Using policy documents, academic material, and the popular press, we show that Ghana’s policy focus on sugar production and tomato processing has endured, despite the fact that the factories were misconceived, poorly sited, ill-equipped and poorly managed. Indeed, the political ideas that underpinned the establishment of these factories in the early days of independence can be seen in the current One District, One Factory policy. We suggest that it is their symbolic and political value, not their economic value, which keeps the discussion around these factories alive. Even when shut down, they are a physical manifestation of historic commitments by the state, and as such they guarantee the attention of politicians, and hold out hope of a next re-launch. Unfortunately as long as the factories continue to be incorporated into each new generation of agro-industrial policy, it is difficult for any alternatives to gain traction. This analysis highlights the very long overhang of bad decisions, particularly when they are associated with physical infrastructure. Learning from past mistakes will only happen if the short-term political cost of turning policy learning into policy action can be overcome.  相似文献   
2.
ABSTRACT

This paper aims to explore the conceptual potential of the Deleuzian notion of the encounter in order to better understand the genealogy of opportunities. We adopt a processual perspective of opportunities. In order to translate this notion to the domain of entrepreneurship, we analysed and interpreted Jean-Marc Vallée’s Dallas Buyers Club. This film follows the creation of the first club in the United States that illegally allowed HIV-positive people to supply themselves with foreign antiretroviral drugs from Mexico or Japan. The article highlights encounters in this process that disturb the entrepreneur’s belief systems and allow him or her to be open to potential opportunity. It finally explores how the encounter may improve our understanding of the political becoming of opportunities within the entrepreneurial process.  相似文献   
3.
This study examines the sources of labor productivity growth dynamics in Japan (1970–2010) and investigates the extent to which Japanese economic performance has been affected by Baumol's growth disease (BGD). We find that BGD silently undermines Japanese economic growth. However, the magnitude is miniscule, and consequently the aggregate labor productivity growth rate has not been decreasing monotonically. We also explore how BGD is arising and why it is small in the Japanese economy. BGD is weak because (1) the positive Baumol growth effect is also working in certain services sectors and (2) BGD is not a durable phenomenon: even if a sector begins to suffer from BGD, it is likely to recover quickly.  相似文献   
4.
This study investigates the contribution of modern communication infrastructure characterized by high speed broadband access network on the productivity growth, production structure and factor demands for US industries and for the aggregate economy. To evaluate such contribution, we modify the traditional cost function by incorporating communication infrastructure as input in production process in conjunction with other public infrastructures. The network externality and spillover effect of broadband access technology are captured by introducing broadband penetration rate as a shift factor in industry level production function. Empirical results show that the increased use of modern communications infrastructure increases the productivity of all industries with wide variations across industries. Estimated impacts on input demands show that increase in use of communications infrastructure service saves labor and materials and increase the demand for private capital. Finally, aggregate social rate of return on such investment has been estimated for policy implications.  相似文献   
5.
We introduce a new numerical method called the complex Fourier series (CFS) method proposed by Chan (2017) to price options with an early-exercise feature—American, Bermudan and discretely monitored barrier options—under exponential Lévy asset dynamics. This new method allows us to quickly and accurately compute the values of early-exercise options and their Greeks. We also provide an error analysis to demonstrate that, in many cases, we can achieve an exponential convergence rate in the pricing method as long as we choose the correct truncated computational interval. Our numerical analysis indicates that the CFS method is computationally more comparable or favourable than the methods currently available. Finally, the superiority of the CFS method is illustrated with real financial data by considering Standard & Poor’s depositary receipts (SPDR) exchange-traded fund (ETF) on the S&P 500® index options, which are American options traded from November 2017 to February 2018 and from 30 January 2019 to 21 June 2019.  相似文献   
6.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
7.
A play-the-winner-type urn design with reduced variability   总被引:1,自引:0,他引:1  
We propose a new adaptive allocation rule, the drop-the-loser, that randomizes subjects in the course of a trial comparing treatments with dichotomous outcomes. The rule tends to assign more patients to better treatments with the same limiting proportion as the randomized play-the-winner rule. The new design has significantly less variable allocation proportion than the randomized play-the-winner rule. Decrease in variability translates into a gain in statistical power. For some values of success probabilities the drop-the-loser rule has a double advantage over conventional equal allocation in that it has better power and assigns more subjects to the better treatment. Acknowledgments. I thank Stephen Durham, the associate editor, and the referees for their helpful suggestions.  相似文献   
8.
This paper presents qualitative and exploratory research investigating the role that managing knowledge and information plays in new product development (NPD). A set of 20 in-depth interviews uncovered eight basic types of information used throughout the NPD process and three general approaches to managing information needed in the NPD process. Although some exemplary companies seem to do an outstanding job of collecting and disseminating information, the majority of firms struggle. NPD process automation solutions tackle part of the problem, ignoring nonquantitative data forms and the full picture of information use throughout the entire development process.  相似文献   
9.
以创新创业基地建设促进物流实验室发展   总被引:2,自引:0,他引:2  
该文主要阐述了怎样通过建设一个创新创业基地的架构,即管理思路、组织原则、创新流程等一系列实验室管理模式,来提供给管理类大学生一个得到实践锻炼的良好平台,同时也促进管理类专业实验室合理有效的管理。  相似文献   
10.
The question this paper investigates is whether or not different metropolitan areas each constitute a separate housing market or whether or not there is a single South African housing market. Theory on the Law of One Price suggests that if products or geographic areas belong in the same market, their absolute prices must converge, so that their relative prices are stationary. By using cross-sectional time series data of five metropolitan areas, the paper tests for the Law of One Price by applying the Im, Pesaran and Shin panel unit root test. The paper finds strong evidence of convergence in large middle-segment house prices and weaker support for convergence in medium middle-segment house prices. In addition, the paper finds no evidence for convergence in small middle-segment house prices. This suggests the existence of a national market for large and possibly middle-segment houses in metropolitan areas, but separate metropolitan markets for small middle-segment houses. In addition, the paper estimates the speed of convergence and finds that large middle-segment house prices converge within two to seven quarters, while the speed of convergence for medium middle-segment house prices in three of the five areas is five to eight quarters.  相似文献   
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