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1.
Destination competitiveness is the ability to sustain or improve market position and market share of a destination over a period of time. Different markets have different expectations which increase the importance of features a destination should provide in order to achieve competitive advantage. The results of this study show that the domestic model of Iran’s destinations competitiveness comprises 9 major indices. These indices are made of 64 variables which have been derived from literature reviews and qualitative surveys. The results of running the model for all selected destinations are consistent with the destinations’ tourist statistics except for one destination (Qom).  相似文献   
2.
《Economic Systems》2021,45(4):100872
According to the conservative view, capital flows enhance economic growth. Focussing on Africa’s real economy, this study investigates the linkage between portfolio investments and real sector growth, and whether financial sector development strengthens this association. The study covers 30 countries over the period 1990–2017. We adopt the Lewbel instrumental variable general method of moments (IV-GMM) two-step robust estimator, which relies on heteroscedasticity for identification, while dealing with instrument insufficiency, unavailability, endogeneity and omitted variable bias. We found that portfolio equity has no growth impact on Africa’s real sector. Debt flows deter the growth of the overall real sector as well as the manufacturing and industrial sectors, but have no impact on agriculture and service growth. We found that financial development does strengthen the positive association between capital flows and economic growth, but this is dependent on the type of sector and portfolio investment, as well as on the degree of financial development. We control for known determinants of economic growth.  相似文献   
3.
Due to the serious increase of environmental pollution in China, environmental regulations have become significantly stringent. Such regulations are playing an increasingly important role in the development of small enterprises (SEs) in China, especially in SEs' market entry. However, existing studies pay little attention to this issue. This paper investigates for the first time the effect of environmental regulations on SEs' market entry and the mechanism of environmental regulation effects in China. We consider two sets of panel data for the periods 2003–2010 and 2012–2015 in China. We also use the fixed effect model and the instrumental variable method to explore the role of environmental regulations in SEs' market entry. The results show that, overall, environmental regulations play a significantly positive and robust role in SEs' market entry. However, the mechanisms associated with the effect of environmental regulations on different innovative types of SEs differ. Environmental regulations promote the market entry of SEs with product innovation, but this impact is not significant for SEs with research and development (R&D) activities and R&D institutions. Our findings indicate that China's SEs prefer product innovation, which is a lower level innovative type, over R&D innovation, as a means to avoid the negative impact of stringent environmental regulations.  相似文献   
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5.
盐城市水资源承载状态预警研究   总被引:2,自引:1,他引:1  
在分析水资源承载状态预警概念的基础上,引入"三类六级"预警思想,采用可变模糊法和层次分析法的思想,构建盐城市水资源承载状态综合预警指标体系,评价盐城市2015年、2020年和2030年的水资源承载状态,并结合各年份承载状态变化趋势,对未来年份进行预警。结果表明:盐城市2015年水资源处于临界超载的状态,但随着"关于做好建立全国水资源承载能力监测预警机制工作的通知"等一系列措施的实施,2020年、2030年承载状态将逐步好转,到2030年将处于可载的状态。  相似文献   
6.
利用辐射源目标的频移动态特征进行盲分选时,针对已有的分选方法不能很好解决非合作接收数据非周期、间断、交叠的问题,提出了一种改进的逻辑回归分选算法,将信号分选转化为轨迹分类的问题来处理。首先,借鉴多目标航迹起始模型中的M/N逻辑法的框架,设计新的数据关联门限,以建立目标起始曲线;其次,采用最小二乘拟合方法替代卡尔曼滤波,设计新的外推规则,建立载频变化预测曲线;分析新的接收数据与预测曲线的关联性,不断迭代回归或形成新的分支,最后获得目标分选结果。仿真与实测试验表明,利用逻辑回归分选算法,对不同运动目标搭载的同频辐射源可进行自动分选,4个仿真目标与2个真实目标的分选正确率达到100%。同时,该方法拓展了辐射源目标盲分选中的动态频移特征应用,为辐射源个体识别提供了新的支持。  相似文献   
7.
This paper estimates the causal effect of fiscal rules on fiscal balances in a panel of 142 countries over the period 1985–2015. Our instrumental variable strategy exploits the geographical diffusion of fiscal rules across countries. The intuition is that reforms in neighboring countries may affect the adoption of domestic reforms through peer pressure and imitational effects. We find that the mere existence of fiscal rules correlates with lower deficits, but the positive link disappears when endogeneity is correctly addressed. However, when considering the strength of rules through a continuous index of fiscal rules’ design, we show that well-designed rules have a statistically significant impact on fiscal balances. We conduct several robustness tests and show that our results are generally robust and not affected by weak instrument problems.  相似文献   
8.
This article estimates agglomeration effects via calculating EG (Elilsion & Glaeser) and TFP growth (Total Factor Production) by considering the undesired output of the industrial enterprise database and the entropy weight method. Using panel data of 207 county-level cities in China and 28 two-digit manufacturing industries from 2003 to 2013 based on SIC codes, this paper analyzes the relationship between agglomeration and TFP growth through the smooth transition model under different regions and factor-intensity. The results are as follows. (1) A negative relationship appears in manufacturing productivity. The agglomeration effect changes to the crowded effect. Environmental pollution is also generated by transportation and inadequate pollution treatment technology. (2) The excessive agglomeration phenomenon of developed areas (eastern region) is less than the less developed areas (central and western regions). (3) Resource-intensity industries present two thresholds that indicate complex regional features. For various intensive industries in different regions, the relationship between GML and agglomeration is different. High agglomeration does not always promote TFP growth. (4) At different levels of urban industrial agglomeration, the influences of efficiency change and technical change on GML are different. Overall, moderate agglomeration in all regions helps promote economic development.  相似文献   
9.
Female labour force participation rates across the Middle East and North Africa (MENA) region have remained low for over four decades even though, in the same period, women's education rapidly increased and fertility rates substantially decreased. This study provides a better understanding of this surprising phenomenon by testing whether the number of children affects the mother's labour supply (using twins at first birth as an instrumental variable.) Despite a strong first stage, it does not find statistically significant effects in the second stage, even in the combined sample of over 100,000 observations. This non‐result, however, does not rule out that fertility affects women's employment in these countries. But it rejects impacts larger than 0.09. Similar twin‐studies in the United States found effects between 0.12 and 0.31. The paper discusses the implications of this result in understanding the puzzle of female participation in MENA and in designing policies to increase women's employment.  相似文献   
10.
Drought and high temperatures are major threats to sustainable food production and consequently the livelihoods of the majority of Africans who depend on fragile agricultural systems. As a response to these threats, climate-smart agricultural technologies, such as drought-tolerant maize (DTM) varieties, have been developed and promoted on the continent. It is well-known that the adoption of improved technologies generally impacts positively on the wellbeing of adopters. Nevertheless, the magnitude of the impact of any technology or intervention is always an empirical question. Therefore, this study sought to determine the factors that influence the adoption of DTM and subsequently estimate how yield, commercialization intensity, and farm income are affected by adoption. To establish causation, we relied on observations from 200 farm households in the Northern Region of Ghana and estimated an instrumental variable regression. Consistent with findings reported in the literature, we found that DTM adoption is primarily driven by access to seed, extension service, labor availability, and location of farm households. In addition, we found that DTM adoption positively impacts on yield and commercialization intensity. The magnitude of impact is not trivial. For example, the yield of farm households increased by more than 150% (936 kg/ha) following DTM adoption. These results imply that policy-makers and development practitioners must support research and promotion of climate-smart agriculture to improve adoption and welfare indicators, such as yield and commercialization.  相似文献   
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