资源错配、要素市场总扭曲及福利损失测算*——基于单位要素成本的生产率分解视角

通过引入单位要素成本指标,本文对佩特兰和勒文叟汉（Petrin and Levinsohn）的生产率分解模型进行了拓展,［1］得到了一个更为准确的资源重置效应。利用2000—2007年中国规模以上制造业企业数据,经过测算显示,技术进步和要素市场总扭曲是生产率增长的主要来源;样本期间资源重置对生产率增长的平均贡献仅有324%,且日渐式微。然而资源错配造成的福利损失却依旧占制造业增加值的近2663%。这表明,在现有体制下通过市场自发调节促进要素合理配置的空间已经耗尽,经济结构呈现出一定的“固化”倾向,进一步的资源重置应来自对现有经济结构的改革,以缓解资源错配。本文最后通过测算各地区的资源重置潜力,为区域结构优化提供了一个量化参考。     

中国房地产泡沫到底有多大

利用Ramsey模型，采取资本边际收益率法，实证测试了2000～2004年我国房地产的泡沫度，得出了期间我国房地产经历了从负泡沫、无泡沫到正泡沫演变的结论。     

探析横管式煤气初冷器阻力大的原因及应对措施

在焦化行业内,炼焦过程必将产生大量焦炉荒煤气,采用煤气鼓风对焦炉荒煤气进行处理就成为工作重点,不仅能够促进环境的改善,还可以回收荒煤气中大量的化工原材料,并带来较大的经济效益。但在焦化厂实际生产中,横管式煤气初冷器常常因阻力过高发生故障,对煤气鼓风机的正常运作形成干扰,造成装置沉积物阻塞与环境污染等问题。论文以湖北中平鄂钢联合焦化有限责任公司的横管式煤气初冷器为实例,简要分析阻力增大的原因及应对措施。     

卷烟企业制丝线管控目标分析与设计

文章基于制丝线管理目标需求进行系统目标分析,分解系统结构并且进行优化设计,旨在改善制丝线管控目标控制效果,提高生产效能。     

Do Institutions Cause Growth?

We revisit the debate over whether political institutions cause economic growth, or whether, alternatively, growth and human capital accumulation lead to institutional improvement. We find that most indicators of institutional quality used to establish the proposition that institutions cause growth are constructed to be conceptually unsuitable for that purpose. We also find that some of the instrumental variable techniques used in the literature are flawed. Basic OLS results, as well as a variety of additional evidence, suggest that (a) human capital is a more basic source of growth than are the institutions, (b) poor countries get out of poverty through good policies, often pursued by dictators, and (c) subsequently improve their political institutions.     

我国蛋鸡养殖环境全要素生产率测度及省域比较分析

［目的］蛋鸡养殖场规模化养殖与生态环境保护协调发展问题是蛋鸡养殖业可持续发展过程中面临的关键性问题,测度我国大、中、小3种规模下不同省份蛋鸡养殖场的环境全要素生产率,并从时间、地区两个维度对蛋鸡养殖场的环境全要素生产率进行比较。［方法］利用2004—2016年不同养殖规模蛋鸡养殖场的投入和产出数据,文章基于SBM函数的Malmquist Luengerber（ML）指数方法,对蛋鸡养殖场环境全要素生产率进行分解,将其分解为技术进步指数、效率改进指数。［结果］（1）蛋鸡养殖场环境全要素生产率整体呈现下降趋势,同时与蛋鸡养殖规模呈反比,蛋鸡养殖场规模越大,蛋鸡养殖环境生产率越小。（2）蛋鸡养殖场效率存在效率改善,但养殖技术进步率相对较低,尤其是对小规模养殖场而言,改善空间更明显; （3）蛋鸡养殖环境全要素生产率区域差异较为明显,整体来看,蛋鸡养殖主产区环境全要素生产率高于非主产区。［结论］加强蛋鸡产业科技创新水平以及公共服务设施的投入,提高养殖户的废弃物无害化处理能力,推行蛋鸡养殖的规模化和标准化发展,进一步改善养殖效率,以促进蛋鸡养殖规模化和生态环境保护协调发展。     

Micro-foundation for a constant elasticity of substitution production function through mechanization

We consider an increase in the range of capital use as a form of mechanization. A constant elasticity of substitution (CES) production function is dynamically derived from Leontief production functions through the endogenous complementary relationship between capital accumulation and mechanization. This implies that a CES production function can be resolved into technological change that does not involve changes in total factor productivity. Furthermore, using the normalizing procedure of the CES production function developed by de La Grandville [de La Grandville, O., 1989. In quest of the Slutsky diamond. American Economic Review 79, 468–481], we investigate how mechanization is related to the elasticity of substitution in our endogenous growth model.     

European financial crisis and bank productivity: evidence from Eastern European Countries

The paper examines the productivity levels of the largest banks operating in the Eastern European countries over the period of the ongoing European financial crisis. Specifically, the analysis covers the periods of U.S. subprime crisis, the global financial crisis and the sovereign debt crisis. By adopting a fully nonparametric framework, it provides a probabilistic version of a directional input-oriented Malmquist productivity index alongside with its main decomposition. The results from the analysis suggest that banks have faced a deterioration of their productivity levels between the examined periods. It is evident that during the initiation of European sovereign debt crisis, the banks have weakened their ability to utilize efficiently their inputs of production and their ability to realize scale economies.     

Effectiveness and safety of betrixaban extended prophylaxis for venous thromboembolism compared with standard-duration prophylaxis intervention in acute medically ill patients: a systematic literature review and network meta-analysis

Abstract

Aims: To determine the clinical effectiveness and safety of venous thromboembolism (VTE) prophylaxis using US- and Europe-approved anticoagulants relative to extended-duration VTE prophylaxis with betrixaban. Low molecular weight heparins (LMWHs), unfractionated heparin (UFH), fondaparinux sodium and placebo were each compared to betrixaban, as standard-duration VTE prophylaxis for hospitalized, non-surgical patients with acute medical illness at risk of VTE.

Materials and methods: A systematic literature review was conducted up to June 2019 to identify randomized controlled trials (RCTs) of VTE prophylaxis in hospitalized, non-surgical patients with acute medical illness at risk of VTE. Studies that reported the occurrence of VTE events (including death) and, where possible, major bleeding, from treatment initiation to 20–50?days thereafter were retrieved and extracted. A Bayesian fixed effect network meta-analysis was used to estimate efficacy and safety of betrixaban compared with standard-duration VTE prophylaxis.

Results: Seven RCTs were analyzed which compared betrixaban, LMWHs, UFH, fondaparinux sodium, or placebo. There were significantly higher odds (median odds [95% credible interval]) of VTE with LMWHs (1.38 [1.12–1.70]), UFH (1.60 [1.05–2.46]), and placebo (2.37 [1.55–3.66]) compared with betrixaban. There were significantly higher odds of VTE-related death with placebo (7.76 [2.14–34.40]) compared with betrixaban. No significant differences were observed for the odds of major bleeding with all comparators, VTE-related death with any active standard-duration VTE prophylaxis, or of VTE with fondaparinux sodium, compared with betrixaban.

Limitations and conclusions: In this indirect comparison, betrixaban was shown to be an effective regimen with relative benefits compared with LMWHs and UFH. This indicates that betrixaban could reduce the burden of VTE in at-risk hospitalized patients with acute medical illness who need extended prophylaxis, though without direct comparative evidence, stronger conclusions cannot be drawn.     

生产力、生产关系矛盾运动规律新探

生产力、生产关系辩证运动规律是人类社会发展变化的基本规律。长期以来,由于对这一基本规律认识的简单化和绝对化,造成了认识上的混乱。首先,生产力不是“物质力量”,而是人与自然的矛盾关系的统一;其次,生产力的存在方式是客观现实性和社会历史性的统一,与之对应,生产关系也是如此;再次,生产力、生产关系的矛盾运动规律不是“有什么样的生产力,就有什么样的生产关系”,而是生产力的质变必然导致生产关系的质变,生产力的量变也可能导致生产关系的质变,一种性质生产力的存在,可以决定不同性质生产关系同时并存。