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1.
A moral hazard model is used to show why overly optimistic revenue forecasts prior to elections can be optimal: Opportunistic governments can increase spending and appear more competent; ex post deficits emerge in election years, thereby producing political forecast cycles – as also found for US states in the empirical literature. Additionally, we obtain three theoretical results which are tested with panel data for Portuguese municipalities. The extent of manipulations is reduced when (i) the winning margin is expected to widen; (ii) the incumbent is not re-running; and/or (iii) the share of informed voters (proxied by education) goes up.  相似文献   
2.
This paper examines the relationship between the individualism-collectivism dimension of culture and political instability using a dataset covering around 100 countries. To shed light on the causal effect of culture on political instability, the identification strategy exploits the variation in historical pathogen prevalence and the information provided by the genetic distance between countries. The results reveal that individualism has a negative and statistically significant impact on the degree of political instability, which means that this cultural trait contributes to making the political environment more stable. This finding is robust to the inclusion in the analysis of a substantial number of controls that may be correlated with both individualism and political instability, including other cultural dimensions. In fact, the relationship between individualism and political instability does not depend either on the specific measures used to quantify the level of individualism and political instability within the various countries or the estimation strategy adopted. The estimates also show that part of the observed effect of individualism is due to the impact of institutional quality, which acts as a transmission channel linking this cultural trait and political instability.  相似文献   
3.
Innovation clusters combining public and private effort to develop breakthrough technologies promise greater technological advances to slow down climate change. We use a multi-country model with an emission trading system to examine whether and how international climate policy can incentivize countries to create such innovation clusters. We find that a minimal carbon price is needed to attract applied research firms, but countries may nevertheless fail to invest in complementary research infrastructure. We construct a mechanism that leads to innovation clusters when emissions targets are set before uncertainty surrounding technological developments is resolved. It is a combination of low permit endowments for the country with the lowest costs to build the needed infrastructure, compensation for this country by profits from permit trade, and maximal possible permit endowments for the remaining countries. We outline how the EU-ETS can be further refined according to this mechanism.  相似文献   
4.
陈媛  王伟华  王福颖 《科技和产业》2023,23(16):154-159
选取2021年度数据,采用数据包络分析(DEA)方法对中国东部地区10个省份规模以上工业企业的研发投入绩效进行评价,并采用灰关联分析方法分析确定各项研发投入产出指标相对于DEA效率的灰色关联度。研究结果表明,80%的省份规上工业企业研发投入产出处于非DEA有效状态,存在不同程度的投入冗余或产出不足;规上工业企业发明专利申请数与研发投入产出效率的关联度最高,其次是新产品销售收入和R&D经费内部支出。  相似文献   
5.
We add to the ongoing discussion regarding the policy consequences of terrorism by analyzing the effect of terrorism on international economic policy for a panel of 170 countries between 1970 and 2016. We find that countries resort to less liberal international economic policies when facing the threat of terrorism. This effect is especially relevant to smaller (less populated) countries. Our main finding is robust to an instrumental-variable approach. We argue that governments pursue less liberal international economic policies in response to terrorism to interrupt the organization and financing of terrorism, limit capital flight, stabilize public finances and signal political resolve.  相似文献   
6.
Predicting consumption behavior is very important for adjusting supplier production plans and enterprise marketing activities. Conventional statistical methods are unable to accurately predict green consumption behavior because it is characterized by multivariate nonlinear interactions. The paper proposes an optimized fruit fly algorithm (FOA) and extreme learning machine (ELM) model for consumption behavior prediction. First, to address the problem of uneven search direction of FOA leading to insufficient search ability and low efficiency, the paper proposes a sector search mechanism instead of a random search mechanism to improve the global search ability and convergence speed of FOA. Second, to address the issue that the initial weights and hidden layer bias values of the ELM are randomly generated, which affects the learning efficiency and generalization of the ELM, the paper uses an improved FOA to optimize the weights and bias values of ELM for improving the prediction accuracy. Taking the green vegetable consumption behavior of Beijing residents as an example, the results show the optimization of the initial weight and threshold of ELM by the GA, PSO, FOA, and SFOA, the prediction accuracy of the GA-ELM, PSO-ELM, FOA-ELM, and SFOA-ELM models all surpass those of ELM. Compared with BPNN, GRNN, ELM, GA-ELM, PSO-ELM, and FOA-ELM models, the RMSE value of SFOA-ELM was decreased by 9.45%, 8.40%, 11.89%, 5.84%, 2.22%, and 2.69%, respectively. These findings demonstrate the effectiveness of the SFOA-ELM model in green consumption behavior prediction and provide new ideas for the accurate prediction of consumption behaviors of other green products with similar characteristics.  相似文献   
7.
[目的]通过充分发挥移动互联时代消费者对于价值链、创新链、产业链构建的作用,实现价值共创视角下乡村旅游价值链的重构,解决乡村旅游产业中消费者需求和产业供给不平衡不充分之间的矛盾,推动乡村旅游高效、有序、协调、综合发展。[方法]基于价值共创理论,通过文献研究法和系统论方法,探索性重构乡村旅游价值链。[结果](1)价值共创引导下的乡村旅游价值链是由基本价值活动、辅助价值活动和价值共创活动共同组成,通过虚拟价值链和传统价值链的互动与融合,实现乡村旅游价值链的新价值创造。(2)价值共创活动是以虚拟价值链为基本特征,以“产消者”创新社区为表现形式,依托移动互联网时代的先进技术,创新性赋予旅游者产品生产者和旅游消费者的“产消者”双重属性,通过将消费者从传统价值链的幕后拉向幕前,实现乡村旅游价值链重构和价值增值。[结论]价值共创引导的乡村旅游价值链需要依托平台思维、共享思维和创新思维进行建设,以消费者需求为导向形成的价值链的开放和互动对于实现乡村旅游供给侧结构性改革具有重大意义。  相似文献   
8.
窦程强 《技术经济》2020,39(2):55-63
以纳税信用评级披露作为一个天然外生冲击,并基于2013—2016年1214家A股上市公司的微观数据构造准自然实验,使用双重差分法系统评估纳税信用评级结果披露对上市公司研发投入的影响。结果发现:纳税信用评级结果披露显著增加了上市公司的研发投入。基于PSM-DID方法的估计结果与上述结论无明显差异。稳健性检验也表明上述结论的正确性。机制检验表明,纳税信用评级结果披露通过降低企业的融资约束,进而促进企业增加研发投入。此外,分样本回归发现纳税信用评级结果披露只能对中小型企业和民营企业的研发投入产生促进作用。  相似文献   
9.
In this article, we compare two kinds of environmental regulations—emissions taxes and green R&D subsidies—in private and mixed-duopoly markets in the presence of R&D spillovers. We show that a green R&D subsidy is better (worse) than an emissions tax when the green R&D is efficient (inefficient), irrespective of R&D spillovers, whereas the existence of a publicly owned firm encourages the government to adopt a subsidy policy. We also show that the optimal policy choice depends on R&D efficiency and spillovers. In particular, when green R&D is inefficient and the spillover rate is low (high), the government should choose an emissions tax and (not) privatize the state-owned firm. When green R&D is efficient, however, an R&D subsidy is better, but a privatization policy is not desirable for society, irrespective of spillovers.  相似文献   
10.
为实现大规模集成电路中的"自动布线问题",首先针对单层平面内通道自动布线问题使用A*算法,发现上下引脚连接线路发生路径冲突时,单通道自动布线问题无解.对多层数电路通道自动布线使用Floyd算法建模,分别对每层线路进行优化.构建基于遗传算法的A*目标函数最优化自动布线模型,来解决三维空间结构优化、系统整体布线距离优化以及金属线与通孔寄生电阻最小化问题.之后使用样本测例对建立的模型进行验证,提出新的解决路线.  相似文献   
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