Taxation and liability are compared here as means of controlling harmful externalities. It is emphasized that liability has an advantage over taxation: inefficiency of incentives arises under taxation when, as would be typical, it would be impractical for a tax to reflect all variables that significantly affect expected harm, whereas efficiency of incentives under liability does not require the state to determine expected harm - it requires only that injurers pay for harm that occurs. However, taxation enjoys an advantage over liability: incentives under liability are diluted to the degree that injurers might escape suit. The optimal joint use of taxation and liability is also examined, and it is shown in the model that is analyzed that liability should be employed fully because liability creates more efficient incentives than taxation; a tax should be used only to take up the slack due to the possibility that suit for harm would not be brought.
{"title":"Corrective Taxation Versus Liability","authors":"S. Shavell","doi":"10.2139/ssrn.1636357","DOIUrl":"https://doi.org/10.2139/ssrn.1636357","url":null,"abstract":"Taxation and liability are compared here as means of controlling harmful externalities. It is emphasized that liability has an advantage over taxation: inefficiency of incentives arises under taxation when, as would be typical, it would be impractical for a tax to reflect all variables that significantly affect expected harm, whereas efficiency of incentives under liability does not require the state to determine expected harm - it requires only that injurers pay for harm that occurs. However, taxation enjoys an advantage over liability: incentives under liability are diluted to the degree that injurers might escape suit. The optimal joint use of taxation and liability is also examined, and it is shown in the model that is analyzed that liability should be employed fully because liability creates more efficient incentives than taxation; a tax should be used only to take up the slack due to the possibility that suit for harm would not be brought.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115295775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using a discrete-continuous model that deals with both consumers' choice and usage of an environmentally differentiated product in a utility-consistent framework, this paper investigates welfare impacts of emission taxes, subsidies and ad valorem taxes/subsidies on a green market where consumers emit a pollutant through their usage of the products offered by duopolists. An emission tax is always welfare dominant over a subsidy on consumers' purchase of the clean product because the emission tax contributes to a reduction in environmental damage by inducing firms to improve environmental qualities of the products and by constraining consumers' usage of the products. An ad valorem subsidy is always dominated by both an emission tax and a subsidy in terms of social welfare.
{"title":"Environmental Policy in a Vertically Differentiated Product Market","authors":"I. Matsukawa","doi":"10.2139/ssrn.1633382","DOIUrl":"https://doi.org/10.2139/ssrn.1633382","url":null,"abstract":"Using a discrete-continuous model that deals with both consumers' choice and usage of an environmentally differentiated product in a utility-consistent framework, this paper investigates welfare impacts of emission taxes, subsidies and ad valorem taxes/subsidies on a green market where consumers emit a pollutant through their usage of the products offered by duopolists. An emission tax is always welfare dominant over a subsidy on consumers' purchase of the clean product because the emission tax contributes to a reduction in environmental damage by inducing firms to improve environmental qualities of the products and by constraining consumers' usage of the products. An ad valorem subsidy is always dominated by both an emission tax and a subsidy in terms of social welfare.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129738032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-01DOI: 10.1111/j.1467-9701.2010.01287.x
Benito Müller, C. Hepburn
Greenhouse gas emissions from international aviation services have been increasing rapidly and are likely to continue to do so in the absence of major policy changes. At the same time, while all countries will experience impacts from climate change, developing countries are the most vulnerable. Significant financial assistance for adaptation is therefore needed for developing countries, but current proposals are inadequate. Solutions to the challenges of both aviation greenhouse gas emissions and climate change adaptation finance are thus urgently required. This paper proposes an international air travel adaptation levy that addresses both problems.
{"title":"International Air Travel and Greenhouse Gas Emissions: A Proposal for an Adaptation Levy","authors":"Benito Müller, C. Hepburn","doi":"10.1111/j.1467-9701.2010.01287.x","DOIUrl":"https://doi.org/10.1111/j.1467-9701.2010.01287.x","url":null,"abstract":"Greenhouse gas emissions from international aviation services have been increasing rapidly and are likely to continue to do so in the absence of major policy changes. At the same time, while all countries will experience impacts from climate change, developing countries are the most vulnerable. Significant financial assistance for adaptation is therefore needed for developing countries, but current proposals are inadequate. Solutions to the challenges of both aviation greenhouse gas emissions and climate change adaptation finance are thus urgently required. This paper proposes an international air travel adaptation levy that addresses both problems.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114869620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carbon control policies in OECD countries commonly differentiate emission prices in favor of energy-intensive industries. While leakage provides a efficiency argument for differential emission pricing, the latter may be a disguised beggar-thy-neighbor policy to exploit terms of trade. Using an optimal tax framework, we propose a method to decompose the leakage motive and the terms-of-trade motive for emission price differentiation. We illustrate our method with a quantitative impact assessment of unilateral climate policies for the U.S. and EU economies. We conclude in these instances that complex optimal emission price differentiation does not substantially reduce the overall economic costs of carbon abatement compared with a simple rule of uniform emission pricing.
{"title":"Optimal Emission Pricing in the Presence of International Spillovers: Decomposing Leakage and Terms-of-Trade Motives","authors":"Christoph Böhringer, Andreas Lange, T. Rutherford","doi":"10.3386/W15899","DOIUrl":"https://doi.org/10.3386/W15899","url":null,"abstract":"Carbon control policies in OECD countries commonly differentiate emission prices in favor of energy-intensive industries. While leakage provides a efficiency argument for differential emission pricing, the latter may be a disguised beggar-thy-neighbor policy to exploit terms of trade. Using an optimal tax framework, we propose a method to decompose the leakage motive and the terms-of-trade motive for emission price differentiation. We illustrate our method with a quantitative impact assessment of unilateral climate policies for the U.S. and EU economies. We conclude in these instances that complex optimal emission price differentiation does not substantially reduce the overall economic costs of carbon abatement compared with a simple rule of uniform emission pricing.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116218688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Price floors in greenhouse gas emissions trading schemes can have advantages for technological innovation, price volatility, and management of cost uncertainty, but implementation has potential pitfalls. We argue that the best mechanism for implementing a price floor is to have firms pay an extra fee or tax. This has budgetary advantages and is more compatible with international permit trading than alternative approaches that dominate the academic and policy debate. The fee approach can also be used to implement more general hybrid approaches to emissions pricing.
{"title":"Price Floors for Emissions Trading","authors":"P. Wood, F. Jotzo","doi":"10.2139/ssrn.1532701","DOIUrl":"https://doi.org/10.2139/ssrn.1532701","url":null,"abstract":"Price floors in greenhouse gas emissions trading schemes can have advantages for technological innovation, price volatility, and management of cost uncertainty, but implementation has potential pitfalls. We argue that the best mechanism for implementing a price floor is to have firms pay an extra fee or tax. This has budgetary advantages and is more compatible with international permit trading than alternative approaches that dominate the academic and policy debate. The fee approach can also be used to implement more general hybrid approaches to emissions pricing.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124112744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We estimate fiscal reaction functions for non-hydrocarbon tax and public spending shares of national income and for debt management strategies adopted by Norway and compare these with rules that would prevail under the permanent income hypothesis and bird-in-hand rule. We conclude that the fiscal reaction functions adopted by Norway have to some extent been forward-looking when it comes to the rising pension bill, but backward-looking when it comes to hydrocarbon revenues. Still, our results suggest that the imminent costs of a rapidly graying population are not sufficiently taken into account in the current fiscal rules, since Norway is on a trajectory of turning a current net asset-GDP-ratio close to one into a net debt-GDP-ratio of two in 2060. Something needs to give in the holy trinity: either the rules of the Stabilization fund have to be tightened, or civil servant salaries, benefits and pensions will no longer have to be fully indexed to market wages, or the retirement age has to be increased.
{"title":"Is Norway's Bird-in-Hand Stabilization Fund Prudent Enough? Fiscal Reactions to Hydrocarbon Windfalls and Graying Populations","authors":"Torfinn Harding, Rick van der Ploeg","doi":"10.2139/ssrn.1494895","DOIUrl":"https://doi.org/10.2139/ssrn.1494895","url":null,"abstract":"We estimate fiscal reaction functions for non-hydrocarbon tax and public spending shares of national income and for debt management strategies adopted by Norway and compare these with rules that would prevail under the permanent income hypothesis and bird-in-hand rule. We conclude that the fiscal reaction functions adopted by Norway have to some extent been forward-looking when it comes to the rising pension bill, but backward-looking when it comes to hydrocarbon revenues. Still, our results suggest that the imminent costs of a rapidly graying population are not sufficiently taken into account in the current fiscal rules, since Norway is on a trajectory of turning a current net asset-GDP-ratio close to one into a net debt-GDP-ratio of two in 2060. Something needs to give in the holy trinity: either the rules of the Stabilization fund have to be tightened, or civil servant salaries, benefits and pensions will no longer have to be fully indexed to market wages, or the retirement age has to be increased.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130152030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper measures the incidence of a carbon tax on gasoline using current income and two measures of lifetime income to rank households. Our results suggest that carbon taxes on gasoline are more regressive when annual income is used as a measure of economic welfare than when lifetime income measures are used. In addition we find that the regional variation in the gasoline tax burden is likely to be modest varying by less than one-half of a percentage point with little fluctuation over the years of our analysis. These results carry through when we consider the incidence of the current state gasoline taxes, both across income deciles as well as across regions.
{"title":"The Consumer Burden of a Carbon Tax on Gasoline","authors":"K. Hassett, Aparna Mathur, G. Metcalf","doi":"10.4324/9781936331925-8","DOIUrl":"https://doi.org/10.4324/9781936331925-8","url":null,"abstract":"This paper measures the incidence of a carbon tax on gasoline using current income and two measures of lifetime income to rank households. Our results suggest that carbon taxes on gasoline are more regressive when annual income is used as a measure of economic welfare than when lifetime income measures are used. In addition we find that the regional variation in the gasoline tax burden is likely to be modest varying by less than one-half of a percentage point with little fluctuation over the years of our analysis. These results carry through when we consider the incidence of the current state gasoline taxes, both across income deciles as well as across regions.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115469772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper explores in a general equilibrium framework the welfare and sectoral implications of an optimally designed system of border tax adjustments (BTA) on the imports of energy-intensive industries. Recently, several propositions have been made by policy makers and researchers to use BTA as a restrictive trade policy instrument to address the loss of competitiveness induced by unilateral stringent domestic pollution control policies. In this paper, we define the loss of competitiveness not as a loss of output by domestic energy-intensive producers, but instead as a loss of their market shares. We argue and we show using the Canadian economy as illustration that the most often proposed BTA, which is based on the carbon embodiment of the import good, may under- or over-achieve the objective of addressing the competitive disadvantage of domestic energy-intensive industries. In some cases, the proposed BTA may over protect the domestic energy-intensive industries by providing implicit subsidies as they might even increase their production in the presence of carbon taxes. Similarly, the proposed BTA may fail to fully restore the competitiveness of domestic producers, vis-a-vis their foreign peers. We determine the optimal BTAs on imports that fully restore the competitiveness of domestic firms following unilateral stringent pollution control policies. The ‘optimal’ BTAs take into consideration the general equilibrium effects of the carbon tax and of the import charges on the prices of domestic goods. In most cases, the impact their impact on import prices is higher than in the previous case. As a consequence, they entail higher distortions on resource allocation in the economy and hence higher welfare cost to households.
{"title":"Pollution Control, Competitiveness, and Border Tax Adjustment","authors":"Terry Eyland, Yazid Dissou","doi":"10.2139/ssrn.1508681","DOIUrl":"https://doi.org/10.2139/ssrn.1508681","url":null,"abstract":"This paper explores in a general equilibrium framework the welfare and sectoral implications of an optimally designed system of border tax adjustments (BTA) on the imports of energy-intensive industries. Recently, several propositions have been made by policy makers and researchers to use BTA as a restrictive trade policy instrument to address the loss of competitiveness induced by unilateral stringent domestic pollution control policies. In this paper, we define the loss of competitiveness not as a loss of output by domestic energy-intensive producers, but instead as a loss of their market shares. We argue and we show using the Canadian economy as illustration that the most often proposed BTA, which is based on the carbon embodiment of the import good, may under- or over-achieve the objective of addressing the competitive disadvantage of domestic energy-intensive industries. In some cases, the proposed BTA may over protect the domestic energy-intensive industries by providing implicit subsidies as they might even increase their production in the presence of carbon taxes. Similarly, the proposed BTA may fail to fully restore the competitiveness of domestic producers, vis-a-vis their foreign peers. We determine the optimal BTAs on imports that fully restore the competitiveness of domestic firms following unilateral stringent pollution control policies. The ‘optimal’ BTAs take into consideration the general equilibrium effects of the carbon tax and of the import charges on the prices of domestic goods. In most cases, the impact their impact on import prices is higher than in the previous case. As a consequence, they entail higher distortions on resource allocation in the economy and hence higher welfare cost to households.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121129086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper addresses the timing and interdependence between innovation and environmental policy in a model of research and development (R&D). On a first-best path the environmental tax is set at the Pigouvian level, independent of innovation policy. With infinite patent lifetime, the R&D subsidy should be constant and independent of the state of the environment. However, with finite patent lifetime, optimal innovation policy depends on the stage of the environmental problem. In the early stages of an environmental problem, abatement research should be subsidized at a high level and this subsidy should fall monotonically over time to stimulate initial R&D investments. Alternatively, with a constant R&D subsidy, patents’ length should initially have a very long life-time but this should be gradually shortened. In a second-best situation with no deployment subsidy for abatement equipment, we find that the environmental tax should be high compared to the Pigouvian levels when an abatement industry is developing, but the relative difference falls over time. That is, environmental policies will be accelerated compared to first-best.
{"title":"Linking Environmental and Innovation Policy","authors":"R. Gerlagh, S. Kverndokk, K. E. Rosendahl","doi":"10.2139/ssrn.1158443","DOIUrl":"https://doi.org/10.2139/ssrn.1158443","url":null,"abstract":"This paper addresses the timing and interdependence between innovation and environmental policy in a model of research and development (R&D). On a first-best path the environmental tax is set at the Pigouvian level, independent of innovation policy. With infinite patent lifetime, the R&D subsidy should be constant and independent of the state of the environment. However, with finite patent lifetime, optimal innovation policy depends on the stage of the environmental problem. In the early stages of an environmental problem, abatement research should be subsidized at a high level and this subsidy should fall monotonically over time to stimulate initial R&D investments. Alternatively, with a constant R&D subsidy, patents’ length should initially have a very long life-time but this should be gradually shortened. In a second-best situation with no deployment subsidy for abatement equipment, we find that the environmental tax should be high compared to the Pigouvian levels when an abatement industry is developing, but the relative difference falls over time. That is, environmental policies will be accelerated compared to first-best.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130885930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-05-01DOI: 10.1111/j.1467-9701.2010.01285.x
Ben Lockwood, J. Whalley
We discuss emerging proposals for border tax adjustments (BTAs) to accompany commitments to reduce carbon emissions in the EU, the US and other OECD economies. The rationale offered for such border adjustment is that various entities, such as the EU, if making commitments to reduce emissions which go beyond those undertaken in other regions of the world, impose added costs on domestic producers which create a competitive disadvantage for them. Some form of remedy is viewed as reasonable to maintain the competitiveness of domestic industries when responding to global environmental problems. In this paper, we argue that despite its current carbon manifestation, the issue of border tax adjustments and both their rationale and their effects on trade are not new and, despite the present debate (which seems to overlook older literature), have arisen before. Earlier debate on border tax adjustments occurred at the time of the adoption of the Value Added Tax (VAT) in the EU as a tax harmonization target in the early 1960's. But academic literature of the time showed that a change between origin and destination basis in the VAT would be neutral and hence the use of a destination based tax in the EU to accompany the VAT offered no trade advantage to Europe. Here we argue that essentially the same arguments also apply for carbon motivated BTAs, and in the current debate there seems to be a misconception between price level effects and relative price effects stemming from a BTA, which needs correcting. We also argue that the impact of border tax adjustments should be viewed as independent of the motivation of the adjustments.
{"title":"Carbon-Motivated Border Tax Adjustments: Old Wine in Green Bottles?","authors":"Ben Lockwood, J. Whalley","doi":"10.1111/j.1467-9701.2010.01285.x","DOIUrl":"https://doi.org/10.1111/j.1467-9701.2010.01285.x","url":null,"abstract":"We discuss emerging proposals for border tax adjustments (BTAs) to accompany commitments to reduce carbon emissions in the EU, the US and other OECD economies. The rationale offered for such border adjustment is that various entities, such as the EU, if making commitments to reduce emissions which go beyond those undertaken in other regions of the world, impose added costs on domestic producers which create a competitive disadvantage for them. Some form of remedy is viewed as reasonable to maintain the competitiveness of domestic industries when responding to global environmental problems. In this paper, we argue that despite its current carbon manifestation, the issue of border tax adjustments and both their rationale and their effects on trade are not new and, despite the present debate (which seems to overlook older literature), have arisen before. Earlier debate on border tax adjustments occurred at the time of the adoption of the Value Added Tax (VAT) in the EU as a tax harmonization target in the early 1960's. But academic literature of the time showed that a change between origin and destination basis in the VAT would be neutral and hence the use of a destination based tax in the EU to accompany the VAT offered no trade advantage to Europe. Here we argue that essentially the same arguments also apply for carbon motivated BTAs, and in the current debate there seems to be a misconception between price level effects and relative price effects stemming from a BTA, which needs correcting. We also argue that the impact of border tax adjustments should be viewed as independent of the motivation of the adjustments.","PeriodicalId":176966,"journal":{"name":"ERN: Externalities; Redistributive Effects; Environmental Taxes & Subsidies (Topic)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134608230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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