The effects of public spending externalities

We conduct a positive analysis on the effects of ‘externalities’ produced by government spending. To this effect, we estimate, using U.S. data, an RBC model with two salient features. First, we allow government consumption to directly affect the marginal utility of consumption. Second, we allow public capital to shift the productivity of private factors. We provide an identification analysis that supports the strategy adopted for estimating the parameters governing these two channels. On one hand, private and government consumption are robustly estimated to be substitute goods. Because of substitutability, labor supply reacts little to a government consumption shock, so the estimated output multiplier is much lower than in models with separabilities. On the other hand, our results point towards public investment being ‘unproductive’.     

上海市交通拥堵成本测算及对策研究

依据美国德克萨斯运输学院交通拥挤外部成本的经典测算模型，将交通运输拥挤成本分为时间延误成本、额外燃油消耗成本、环境污染物排放成本和噪音成本三个方面，对于2015年上海市工作日高峰期交通拥挤的外部成本进行了详细的测算。结果表明，交通拥堵的外部成本约占当年上海市GDP的0.63%。最后，对于交通拥堵成本较高的现状提出了包括对上海市部分高度拥堵路段或区域收取拥堵费、大力发展上海市公共交通和发展交通快慢型出行方式共存在内的相关政策和建议。     

对大企业外部性问题的研究

在带来巨大经济效益和高速经济增长的同时,大企业的外部性问题因其大规模生产和消费对整个社会和自然环境造成了严重的负面影响。同时对外部性问题的监测手段和技术的不断提升,以及社会大众对外部性问题的强烈关注,迫使大企业在政府监管督促的基础上,应该发挥其主观能动性,积极将其外部性问题内化。     

日本福岛核泄漏事件风险评估

本文分析了日本福岛第一核电站核泄漏的情况和放射性物质可能扩散到我国的途径,并对日本福岛核泄漏事件对我国的影响进行了风险评估。最后结论为：根据目前的情况,日本福岛核泄漏事件不会危害我国公民的健康。     

国防支出对经济增长的外部性效应及规模效应的分析

本文采用两部门外部性模型,研究中国国防开支对经济增长的外部性效应及规模效应,利用1978-2008年时间序列数据进行了实证分析,并且与学术界1960-2000年的研究结果做了对比。1978-2008期间的实证研究结果表明:规模效应为负,外部性效应为正。     

Sustainability and externalities: Is the internalization of externalities a sufficient condition for sustainability?

In an important contribution in Ecological Economics, van de Bergh (2010) correctly concludes that sustainability does not imply zero externalities. However, he continues with the Delphic statement "(Delphic statements were uttered by the renowned oracle of ancient Greece at Delphi. They were phrased in such a way as to be self-fulfilling because alternative interpretations covered every possibility.)" "Without externalities the problem of sustainability vanishes". If this statement refers to an impossible economic process that produces no externalities then he is right. However, it might be interpreted as stating that whenever environmental policy internalizes environmental externalities then sustainability will be ensured. In this note, I assert that in the real world where externalities prevail, their internalization or neutralization in the traditional way cannot lead to sustainability. Only if internalization takes a very specific form that results in the inviolable preservation of environmental rights of future generations in pure biological terms can sustainability be ensured. After revised the original commentary I resubmit it. The issues raised by the editor have been carefully considered.     

Utilizing environmental information and pricing strategies to reduce externalities of tourism: the case of invasive species in the Galapagos

The increase in demand for nature-based tourism brings economic and educational benefits but risks the introduction of invasive species. Increasing the length of tourist trips can better balance these benefits and risks by maintaining revenues while reducing the number of unique contacts with tourists. Changing the relative prices of trips can induce tourists to take longer trips. We hypothesized that providing information about the negative externalities of tourism could improve the effectiveness of such pricing strategies.

We administered one of two discrete choice surveys to tourists considering a trip to the Galapagos. One of the surveys described the Galapagos as a fragile ecosystem susceptible to invasive species; the second described it as a standard nature-based destination. For each sample, we estimated the probability of the tourist choosing a short versus long trip, given the tourist's personal information and trip options presented to him. We then simulated the demand for trips using three pricing strategies. We found that providing information on invasive species significantly increased the efficacy of strategic pricing. We propose using a two-prong approach to tourism management: educate potential tourists about the islands’ vulnerabilities, and simultaneously increase the per-day cost of short trips relative to that of longer trips.     

Industrialization and environmental externalities in a Solow-type model

In this paper we examine the role played by environmental externalities in shaping the dynamics of an economy with two sectors (a farming sector and an industrial one), free inter-sectoral labor mobility and heterogeneous agents (workers/farmers and industrial entrepreneurs). We find that, in the presence of the environmental pressure of the economic activity of the industrial sector, the stability properties of the equilibria and their features in terms of environmental preservation, welfare outcomes and sectoral allocation of labor are sensitive to the level of carrying capacity. We show that an endogenous process of industrialization associated with a reduction in farmers/workers׳ welfare can emerge.     

各类火灾探测器原理分析及应用探讨

火灾探测器能在火灾发生初期,将燃烧物产生的烟雾、热量、火焰等物理量变成电信号传输到火灾报警控制器,是现代消防系统的核心部件。文章通过对各类火灾探测器的工作原理进行分析,并对其应用场合进行探讨,为火灾自动报警系统的设计、施工与运行维护提供参考依据。     

Internal and external factors in innovation persistence

This paper contributes to the analysis of the persistence of innovation activities, as measured by total factor productivity (TFP), and explores its internal and external determinants stressing its path-dependent characteristics. The external conditions, namely the quality of local knowledge pools and the strength of the Schumpeterian rivalry, along with the internal conditions (the actual levels of dynamic capabilities, as proxied by wage levels and firm size) exert a specific and localised effect upon the persistent introduction of innovations. A multiple transition probability matrixes (MTPMs) approach has been implemented to capture the contingent effects of external factors on long-term innovation persistence. The empirical analysis of the dynamics of firm-level TFP for a sample of approximately 7000 Italian manufacturing companies observed during the years 1996–2005 is based on both the comparison of different transition probability matrixes and on dynamic discrete choice panel data models. The evidence provided by the test of MTPMs in sub-periods suggests that innovation persistence is path-dependent, as opposed to past-dependent.