Open-Air Quarries in the Urban Commune of Zinder (South-East Niger): An Opportunity with Strong Externalities

The framing of this theme would contribute to a better analysis of the benefits of open-air quarrying in Zinder, and should make it possible to understand and measure the socio-environmental externalities of this type of activity in an urban environment. The approach method consisted of carrying out surveys combined with field observations and interviews with the various stakeholders as well as the local population. The results obtained made it possible to identify both positive and negative impacts. The positive impacts are above all the advantages derived from these aggregate quarries, in particular, the creation of direct and permanent jobs and the increase in community income. The price of piling up a truck costs around 28,000 CFA ($56 CAN) and that of loading is around 10,000 F CFA ($20 CAN). This has the effect of removing young people (20 - 39 years old) from the circuit of migration outside the region and even the country. The possibility of using the extraction sites by the local population was identified, in terms of profits relating to fish farming, off-season crops, animal drinking and reclaimed plots. The study also noted negative externalities, such as the temptation of young boys to become involved in extractive activities for immediate gains at the expense of school attendance. Added to this is the upheaval in the topography of the urban landscape, pollution and nuisances (noise, visual and olfactory), while the disappearance or clogging of quarry ponds is the cause of frequent flooding in the neighborhoods. In short, corrective measures (e.g. the revegetation of sites) certainly make it possible to minimize the harmful impacts on the urban environment. But, to improve the performance and organizational capacity of the quarrying industry in Niger, even stronger regulation, training and awareness of stakeholders prove to be the necessary measures.

Assessing the externalities of a ski resort in Tzoumerka:willingness to pay in order to promote or to prevent its construction

The present study aims to assess the externalities of a ski resort,that is planned to be built at Tzoumerka mountains,in Greece.The research relies on the Contingent Valuation method,which indirectly estimates the economic value of environmental and other nonmarket assets,based on the expressed preferences of members of a social group.The investigation was based on primary data.The core idea of questionnaire’s design,is subject to the use of a double WTP(willingness to pay)question,aiming at the monetary assessment of the attitude of the residents,regarding the upcoming infrastructure project,taking into account both its positive and its negative externalities.Depending on the attitude of the survey respondents,they were asked to decide if they wish to offer an amount of money either to promote or to prevent the construction of the ski resort.Parametric and non-parametric models were then applied in order to calculate in economic terms the expressed opinion of the respondents.The primary question to be answered is whether the willingness to build the ski resort holds a higher economic value than the desire to prevent it.According to the results of the survey,the vast majority of residents(92.4%)supported the idea of building the ski resort,projecting their apparent desire for the tourist and economic development of the area.The reinforcement of the construction idea of the project was estimated on average at €378,200.The very low proportion of the participants who disagreed with the project(5%),did not allow the economic assessment of its prevention,leaving room for further research into the application of Contingent Valuation method and its contribution in cost-benefit analysis and decision making,regarding upcoming projects.

Study on Ecological Compensation for Coal Mining Activities Based on Economic Externalities

The development and exploration mode of coal resource activities in China result in tremendous waste of resources and ecological environment pollution problems. This article analyzed the use of economic theory of externalities of coal mining activities from the point of environmental economics principles, proposed the ecological compensation connotation of coal mining activities, and analyzed the feasibility of the implementation of ecological compensation from economic viewpoint.

Industrial Agglomeration Externalities, City Size, and Regional Economic Development： Empirical Research Based on Dynamic Panel Data of 283 Cities and GMM Method

Local governments have long been ardently pursuing the industrial specialization effect(MAR externalities) and industrial diversification effect(Jacobs externalities). Such a pursuit has resulted in severe distortion of resource allocation and negative effect on sustainability of local economic development. Regarding the effect from both MAR and Jacobs externalities on local economic development existing literature records notable disputes. Therefore, for local economic development, one important issue is which externality(MAR or Jacobs) can better bring the effect into play. By studying a panel data of 283 Chinese cities from 2003 to 2012 and applying dynamic plane data GMM method, this paper conducted a regression analysis of the relationship among industrial agglomeration externalities, city size, and regional economic development. The result indicates that with regard to the whole nation, MAR externalities are conducive to regional economy development whereas Jacobs externalities will, to an extent, restrain regional economic development. As regards eastern, middle, and western regions, MAR externalities are conducive only to the economic development of the eastern region; their effects on middle and western regions are insignificant. Moreover, the interaction item between MAR externalities and city size has a significant negative synergistic effect on national economic development and a certain acceleration effect on eastern region as well as a strong negative synergistic effect on the middle region and an insignificant effect on the western region. The interaction item between Jacobs externalities and city size has a positive synergistic effect on only the middle region and has an insignificant synergistic effect on both eastern and western regions. Capital stock and labor input have significant accelerating effects on GDP growth per capita of Chinese cities, whereas material capital and labor input remain primary driving forces for Chinese local economic development. Furthermore, human capital contributes to accelerating urban economic development, whereas government intervention restrains urban economic development.

Externalities, Floating Population and Spatial Agglomeration

With the further development of socialist market economy, the mobility of factor markets in China, especially the labor market, is strengthened. Externalities interacts with the agglomeration of productive factors. Under the framework of new economic geography, this article presents a theoretical model involving the endogenous population density affected by urban externalities. Results show that the population density is more concentrated around the center because the degree and extent of interaction between individuals intensifies when the distance from the center decreases. When there are several externalities resources, the aggregation of externalities changes the configuration of spatial factor allocation. These results fit well with the empirical facts about the decreasing density of floating population along the cities of Guangzhou, Dongguan and Shenzhen in Guangdong Province which is situated in the eastern coast of the Pearl River Delta. We fred that under the impacts of externalities released from Hong Kong into the coast, floating population was more concentrated around Shenzhen and Dongguan, which are more adjacent to Hong Kong compared with Guangzhou City.

Behavior Analysis of Bank into E-Commerce under Network Externalities

With the advent of Internet financial innovation,many commercial banks quietly have started to enter into the Ecommercial in order to prevent oligarchs from eroding financial market.From the perspective of industrial division,this paper reveals the nature of a phenomenon that E-commercial enterprises and banks have stepped into each other's field,which E-commerce of banks can give full play to network effects.Then it uses game theory to analyze the motions of banks to involve into E-commerce and the short-term competitive equilibrium of large incumbent Ecommercial enterprises as well.For individual rationality,the dominant strategy of banks and E-commercial enterprises is(enter,counterattack).Considering network externalities,it constructs a competing model on banks and incumbent E-commercial enterprises and simulates competitive trends and balanced results of their behaviors,which illustrates that banks can obtain network effect after choosing E-commerce strategy.

Using Spatial Econometrics to Measure Ozone Pollution Externalities

This paper summarizes my previous work in Lin (2010), in which I use spatial econometrics to analyze air pollution externalities. In Lin (2010), state-by-state source-receptor transfer coefficients that can be used as a basis for a location- differentiated permit system are estimated. Results affirm the importance of regional transport in determining local ozone air quality, although owing to non-monotonicities in ozone production the externality is not always negative. Because the origin of emissions matters, results also reject a non-spatially differentiated NOx cap and trade program as an appropriate mechanism for reducing ozone smog.

Externalities as Compensatory Criteria of Compulsory Expropriation Actions

Ownership/private property and property inheritance are concepts well-established and constitutionally protected in our modern societies.Nevertheless,numerous provisions in the national legal framework enable the states to expropriate individual private goods under certain severe circumstances through compensation prerequisites.The present manuscript presents a short comparative study of the constitutional articles of many countries,regarding expropriation actions,examines the compensation techniques employed,and interrelates expropriation implementation with economic analysis methods and experimental economics.Furthermore,this paper states that the current Greek expropriate methods consist of an economic disturbance and externality in economic terms.

Does Size Matter？ How Firm Size Affects Social Externalities and Community and Regional Development

This study shows how family firm size affects the extent to which bus and coach operators in Australia interact with and contribute to their community by quantifying the value of eight social externalities and presenting the results, using the number of staff and the number of buses per operator as the denominators. The study highlights how a transaction between the government, as buyer, and the bus operator, as seller of services, can affect an external factor that being community and regional development. The results suggest that the small- and medium-sized family firm bus operators are the governance models most likely to contribute toward achieving community and regional development outcomes, which in turn, highlights the importance placed on the achievement of the non-financial goals of family firms and the socio-emotional wealth of the community in which it is embedded. This study suggests that it is possible that contracting bus-services for social value, rather than just lowest price, would create greater benefit for the community and this would offset any gains in economic efficiency achieved by large and non-family firms.

The Mechanism Behind Urban Population Growth and Shrinkage from the Perspective of Urban Network Externalities

Urban shrinkage is a global phenomenon,and it will coexist with urban growth for many years.At the same time,the network connection between cities continuously improved due to the construction of the transportation and information networks.However,the relationship between urban network externalities and urban population growth/shrinkage remains unclear.Therefore,based on high-speed railway(HSR)flow data,a spatial econometric model is used to explore the mechanism behind urban population growth and shrinkage from the perspective of network externalities in China.The results indicate that:1)the urban network experiences a certain clubbing effect.Growing cities that are strongly connected are concentrated along China’s main railway lines and the southeastern coastal areas,while shrinking cities that are weakly connected are distributed at the periphery of the network.2)Moreover,the network externality disregards spatial distance and together with the agglomeration externality influences the growth and shrinking of cities.3)Urban economic development still promotes the development of Chinese cities.However,the improvement of the urban economy has a negative cross-regional spillover effect on neighboring cities due to urban competition.4)Lastly,Local spillovers of urban network externalities are positive,while cross-regional ones are negative.Consequently,the government needs to promote the construction of multi-dimensional network connections between cities to promote cities’sustainable development.This study reveals the relationship between urban network externalities and urban development,enriches the theories of network externalities and urban growth/shrinkage,and provides a reference for regional coordinated development.

Optimal Separation of Twin Convex Sets under Externalities

This paper studies the outcomes of independent and interdependent pair-wise contests between economic agents subject to an optimal external decision problem for each pair. The external decision maker like the government or regulator is faced with the problem of how to devise rules and regulations regarding contests. In this paper, a decision problem is faced under negative and positive externalities. A pair of entities is represented by disjoint convex sets in a small area in a neighborhood. I assume that each entity imposes an equal externality on the other (and the other only) and thus they can be considered to be twins. Among the group of twins in any neighborhood, there is a set of twin pairs such that, for each pair in the set, each twin can impose a strictly negative externality on the other (and the other only), and this is a potential welfare loss which concerns the decision maker. A separating hyper-plane can block the negative externalities between any pair of twins given convexity. However, this can be costly if positive externality from the neighborhood is also blocked by the separation technology. Thus, this paper compares the pair-wise utility from separation to that of non-separation. A simple representation of the decision problem is developed with respect to a single and isolated neighborhood. A complete characterization of the decision problem is obtained with a large number of pair-wise intersecting neighborhoods.

Decision and Coordination of an E-commerce Supply Chain Considering Returns and Network Externalities

Considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e-commerce supply chain(ECSC)decisions.We show that in the decentralized model,the service level,price,market demand,and ECSC members’profits increase with the network externality strength.However,the service level and price increase,while the market demand and ECSC members’profits decrease with the product return rate.The centralized model is the optimal operating mode when it is properly coordinated.We design the“commission and return cost-sharing”contract to optimize ECSC,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after coordination.Based on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality strength.Through comparisons between the extended and decentralized models,we show that high-quality service can improve ECSC’s profitability,while a high return rate hurts its economic performance.

A decade of Bt cotton in Chinese fields: Assessing the direct effects and indirect externalities of Bt cotton adoption in China

The objective of this study is to examine whether or not the gains from reduced spraying for bollworms are being sustained more than one decade after the initial adoption in 2007. Based on farm-level data collected by the authors in 1999–2007 in 16 villages from 4 provinces, this study shows that insecticides applied for controlling bollworms have declined. This analysis supports Chinese policy makers’ decision to not require refuges of non-Bt cotton fields. It also suggests that past studies may have underestimated the benefits from adopting Bt technology.

A Dynamic Bargaining Game with Externalities

Negotiation and bargaining are the common means of solving economic and political prob-lems.In these problems,players often form coalitions for activities.In the environment with externalities,the worth of a coalition depends not only on itself,but also on the coalition structure of other players.This paper studies dynamic bargaining games with externalities and analyzes the effect of externality on the payoffs of players.Based on the Rubinstein's two-person alternating-offer bargaining game,the authors study a two-person dynamic game with externalities and extend it to the case of n players.The research shows that externality affects the results of this bargaining game,and coalition structures affect the payoffs of players.Players in this bargaining game can always form grand coali- tion if an allocation is effective,but some coalition structures may not be formed under some certain conditions.

Cross-Country Externalities of Trade and FDI Liberalization

We develop a three-country heterogeneous-firm model and show that FDI liberalization in one foreign country （F1） results in the following： （i） some firms from the home country switch from export to FDI in F1; （ii） skilled labor＇s wage rate drops in the home country; （iii） wage inequality between the skilled and unskilled labor decreases; and （iv） some firms from the home country switch from FDI to export to another foreign country （F2）. The effects from trade liberalization are just the opposite, but the effects from education improvement are qualitatively the same as FDI liberalization. The cross-country externalities work through the domestic labor market.

Externalities, Transport Networks and the Economic Growth of Urban Clusters

This article uses network analysis tools and new economic geography theory to modify the rico-classical model of regional economic growth, establishes an economic growth model of urban clusters based on externalities and transport networks through a differentiation of transaction costs, and uses the 1990-2008 data of some Chinese cities and the VAR model to test the model. Our empirical study shows that under the influence of transport networks, central cities rely on factor agglomeration for growth, while peripheral cities catch up quickly; that improved transport networks expedite the factor agglomeration of central cities; and that when some newly-added factors are reserved, increasing the node clustering coefficient and reducing peripheral cities＇ transport costs will promote these cities＇ application of externalities, expedite their economic growth, and facilitate the coordinated growth of central and peripheral cities. Therefore, in building the transport infrastructure, equal emphasis should be placed on linking central cities with peripheral ones and on linking peripheral cities with each other.

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated die-castings.Herein,the development of non-heat treatment Al alloys is becoming the hot topic.In addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of castings.To achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and Ce.Their influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic simulation.Our results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased porosity.Meanwhile,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical properties.Subsequent introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test

BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing.

Service Pricing Decision of E-Commerce Supply Chain Members Considering Diseconomies of Scale and Network Externalities

Considering diseconomies of scale and network externalities in the e-commerce supply chain(ECSC),we construct an e-platform-led benchmark model and derive the optimal decisions.Then,the model is extended by endogenizing the impact of service level on network externalities.Considering service investment that includes fixed and variable investments,the model is further extended.Comparing the extended models with the benchmark model,we found the following conclusions.Although the e-platform dominates the ECSC,its profit is lower than the manufacturer.The corporate profits,service level,and price increase with network externalities.Increases in diseconomies of scale decrease the corporate profits and service level,but increase the price.A high-quality service combined with network externalities can achieve synergy and improve the e-platform’s economies of scale,further generating a higher profit.Improving network externalities promotes the fair profit distributionin ECSC and achieves stable development.

On the Effectiveness and Externalities of the Home Purchase Restriction Policy in China

In order to curb the soaring house prices,the Chinese govemment has been focusing on macro-control of real estate on the demand side.Among them,the Home Purchase Restriction(HPR)is one of the most commonly used policy tools,and its influence has atracted the attention from both the public and the academia.Although many scholars have studied the effectiveness of the home purchase restriction policy,there is n0 universal conclusion and the empirical research on the externalities of this policy is scarce.Based on the daily transaction micro-data of the real estate sales market,the rental market and the land market,this paper uses the difference-in-difference model to evaluate the effectiveness of the HPR more accurately,further integrates the relevance of each market into the analytical framework and explores the externalitics of the HPR on the real estate rental market and the land market.The empirical results show that the HPR lowers the house price by 10.12%,which is higher than the estimation results of previous studies;and increases the rent by 25.09%,while decreases the residential land price by 9.08%,with no significant impact on industrial and commercial land prices.A series of robustness tests and counterfactual analysis,such as PSM-DID,all support the reliability of the empirical results.The extemnalities of the HPR indicates that the policy is not conducive to improving the welfare of pcople with the rigid housing demand,and may tigger the"soft resistance"of the local government.Therefore,the govermment should focus on how to promote the supply-side structural reform on the land market and real estate market on the basis of strengthening the local tax system.