In this paper we investigate the degree of market integration for natural gas in the USA. We perform a rolling cointegration estimation of the city gate gas price and the overall gas price in the USA. The long run adjustment coefficients of all states are reported over a rolling window of 60 month from 1989 to 2013. We can identify eight distinct clusters. Clusters are characterized by a different level adjustment on average. Estimates suggest half-life times ranging from 3 weeks to 6 month. Several regulatory actions in order to liberalize the market of natural gas have an effect in terms of the level relationship. These effects are limited. However, we cannot find these structural breaks in all states. The latest change in exploration technologies, hydraulic fracturing and horizontal drilling, does not yet seem to play an important role to explain price dynamics and market integration.
{"title":"How Integrated are the Local U.S. Markets for Natural Gas? — New Evidence Using Rolling Cointegration","authors":"Tim Böker, Albrecht Michler","doi":"10.3790/AEQ.61.2.175","DOIUrl":"https://doi.org/10.3790/AEQ.61.2.175","url":null,"abstract":"In this paper we investigate the degree of market integration for natural gas in the USA. We perform a rolling cointegration estimation of the city gate gas price and the overall gas price in the USA. The long run adjustment coefficients of all states are reported over a rolling window of 60 month from 1989 to 2013. We can identify eight distinct clusters. Clusters are characterized by a different level adjustment on average. Estimates suggest half-life times ranging from 3 weeks to 6 month. Several regulatory actions in order to liberalize the market of natural gas have an effect in terms of the level relationship. These effects are limited. However, we cannot find these structural breaks in all states. The latest change in exploration technologies, hydraulic fracturing and horizontal drilling, does not yet seem to play an important role to explain price dynamics and market integration.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"175-198"},"PeriodicalIF":0.0,"publicationDate":"2015-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167242","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 empirically investigates the link between productivity and unemployment in a panel of 19 OECD countries between 1970 and 2010. By means of recently developed panel data econometric methods, we find that unemployment and productivity are non-stationary in levels and they are cointegrated for the panel as a whole. In terms of causality, the stronger directional relationship runs from unemployment to productivity. Furthermore, the long-run effect seems to be generally positive, therefore favouring of those theories which suggest that prolonged recessions foster long-run productivity improvements.
{"title":"Panel Causality and Cointegration between Productivity and Unemployment","authors":"J. Jalles","doi":"10.3790/AEQ.61.2.141","DOIUrl":"https://doi.org/10.3790/AEQ.61.2.141","url":null,"abstract":"This paper empirically investigates the link between productivity and unemployment in a panel of 19 OECD countries between 1970 and 2010. By means of recently developed panel data econometric methods, we find that unemployment and productivity are non-stationary in levels and they are cointegrated for the panel as a whole. In terms of causality, the stronger directional relationship runs from unemployment to productivity. Furthermore, the long-run effect seems to be generally positive, therefore favouring of those theories which suggest that prolonged recessions foster long-run productivity improvements.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"141-153"},"PeriodicalIF":0.0,"publicationDate":"2015-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167083","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 discuss properties of alternatives or complements to GDP as a measure of welfare at business cycle frequencies. Our results imply that the suggested indicators show practically no cycle at all and their methodologies can be questioned. First, data are not available at an appropriate quality and frequency. Second, the suggested time series sometimes correlate negatively with each other. Third, cross-section and quasi-panel evidence based on different samples of countries reveals no impact of the stance of the business cycle on some suggested welfare measures. Therefore, alternative welfare measures do not show an equal picture on business cycle frequencies compared to GDP-based measures.
{"title":"Are There Business Cycles \"beyond GDP\"? Alternative Measures to GDP at Business Cycle Frequencies","authors":"Jörg Döpke, Philip Maschke","doi":"10.3790/AEQ.61.2.115","DOIUrl":"https://doi.org/10.3790/AEQ.61.2.115","url":null,"abstract":"We discuss properties of alternatives or complements to GDP as a measure of welfare at business cycle frequencies. Our results imply that the suggested indicators show practically no cycle at all and their methodologies can be questioned. First, data are not available at an appropriate quality and frequency. Second, the suggested time series sometimes correlate negatively with each other. Third, cross-section and quasi-panel evidence based on different samples of countries reveals no impact of the stance of the business cycle on some suggested welfare measures. Therefore, alternative welfare measures do not show an equal picture on business cycle frequencies compared to GDP-based measures.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"115-139"},"PeriodicalIF":0.0,"publicationDate":"2015-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70166987","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}
The relationship between economic growth and income inequality has been extensively investigated by previous studies. However, the studies have produced mixed evidences about the relationship. Previous studied have either exclusively focused on developed countries or on large panels with a larger share of developed than developing economies. In what we believe to be a first effort, in this study we have focused on low-income and high-income developing countries and the economies in transition to ascertain the relationship between economic growth and income inequality. The classification of the countries into the low-income and high-income developing countries and economies in transition are based on the classification of the World Bank as well as our own classification based on an income threshold that is endogenously estimated by our model. The classifications of countries according to their national incomes and stage of their development generate homogeneous samples leading to more robust inference about the relationship between economic growth and income inequality. We have used fixed-effects and dynamic panel technique such as system GMM estimation in our analysis to mitigate endogeneity problem. We have found strong evidence of a negative relationship between economic growth and income inequality in low-income developing countries and strong evidence of a positive relationship between economic growth and income inequality in high-income developing countries and in economies in transition.
{"title":"Developing Countries and Economies in Transition: The Nexus between Economic Growth and Income Inequality","authors":"Fadi Fawaz, Masha Rahnama, Victor J. Valcarcel","doi":"10.3790/AEQ.61.2.155","DOIUrl":"https://doi.org/10.3790/AEQ.61.2.155","url":null,"abstract":"The relationship between economic growth and income inequality has been extensively investigated by previous studies. However, the studies have produced mixed evidences about the relationship. Previous studied have either exclusively focused on developed countries or on large panels with a larger share of developed than developing economies. In what we believe to be a first effort, in this study we have focused on low-income and high-income developing countries and the economies in transition to ascertain the relationship between economic growth and income inequality. The classification of the countries into the low-income and high-income developing countries and economies in transition are based on the classification of the World Bank as well as our own classification based on an income threshold that is endogenously estimated by our model. The classifications of countries according to their national incomes and stage of their development generate homogeneous samples leading to more robust inference about the relationship between economic growth and income inequality. We have used fixed-effects and dynamic panel technique such as system GMM estimation in our analysis to mitigate endogeneity problem. We have found strong evidence of a negative relationship between economic growth and income inequality in low-income developing countries and strong evidence of a positive relationship between economic growth and income inequality in high-income developing countries and in economies in transition.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"155-174"},"PeriodicalIF":0.0,"publicationDate":"2015-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167187","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}
Constant Market Shares Analysis is useful in explaining the gain in export market shares of a country through two terms – structural and competitive effect. However, the model fails to define the type of competitiveness – whether a country is competitive in terms of prices (price competitiveness) or in terms of non-price factors such as quality and variety (non-price competitiveness). This article attempts to improve this analysis by estimating individual price and non-price competitive effect using an export share equation. Our article is original in representing product quality with a ‘knowledge’ variable that reflects the technological know-how of the country including knowledge spillovers from other countries and industries. Using a highly disaggregated industrial trade data over a period of 16 years (1996 to 2011), we find evidence of competitive effects in BRIC exports towards major industrialized countries namely EU-14 (excluding Luxembourg), Japan, United States and Norway. We also find that this gain in export market share is largely attributed to better price competition rather than non-price competition. The industrial results, however, indicate the presence of non-price competitiveness in selected homogeneous product sectors during this period, suggesting the beginning of a shift in BRIC export competitiveness.
{"title":"Analyzing BRIC Competitiveness in the EU-14, Japan, US and Norway","authors":"Thannaletchimy Thanagopal","doi":"10.3790/AEQ.61.3.229","DOIUrl":"https://doi.org/10.3790/AEQ.61.3.229","url":null,"abstract":"Constant Market Shares Analysis is useful in explaining the gain in export market shares of a country through two terms – structural and competitive effect. However, the model fails to define the type of competitiveness – whether a country is competitive in terms of prices (price competitiveness) or in terms of non-price factors such as quality and variety (non-price competitiveness). This article attempts to improve this analysis by estimating individual price and non-price competitive effect using an export share equation. Our article is original in representing product quality with a ‘knowledge’ variable that reflects the technological know-how of the country including knowledge spillovers from other countries and industries. Using a highly disaggregated industrial trade data over a period of 16 years (1996 to 2011), we find evidence of competitive effects in BRIC exports towards major industrialized countries namely EU-14 (excluding Luxembourg), Japan, United States and Norway. We also find that this gain in export market share is largely attributed to better price competition rather than non-price competition. The industrial results, however, indicate the presence of non-price competitiveness in selected homogeneous product sectors during this period, suggesting the beginning of a shift in BRIC export competitiveness.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"229-260"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167392","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}
In this study, we investigate self-financing tax cuts, which are also known as dynamic Laffer effects. By proposing alternative definitions for dynamic Laffer effects, a policy option that features a tax cut should be chosen primarily on the basis of the relative magnitude of government transfers. The simple analytical condition under an alternative financing scheme that leaves current deficits unchanged reduces to a simple comparison between tax revenues and government transfers. Empirical examination of those conditions indicates that whereas countries in Northern and Western Europe, Australia, Canada, New Zealand, Korea, and Mexico show the most potential for experiencing dynamic Laffer effects, countries in Eastern Europe, France, the Netherlands and Portugal were not very susceptible.
{"title":"Simple Analytics of the Dynamic Laffer Curve Under Alternative Financing Schemes","authors":"Y. Tsuchiya","doi":"10.3790/AEQ.61.3.199","DOIUrl":"https://doi.org/10.3790/AEQ.61.3.199","url":null,"abstract":"In this study, we investigate self-financing tax cuts, which are also known as dynamic Laffer effects. By proposing alternative definitions for dynamic Laffer effects, a policy option that features a tax cut should be chosen primarily on the basis of the relative magnitude of government transfers. The simple analytical condition under an alternative financing scheme that leaves current deficits unchanged reduces to a simple comparison between tax revenues and government transfers. Empirical examination of those conditions indicates that whereas countries in Northern and Western Europe, Australia, Canada, New Zealand, Korea, and Mexico show the most potential for experiencing dynamic Laffer effects, countries in Eastern Europe, France, the Netherlands and Portugal were not very susceptible.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"199-227"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167305","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}
In this paper, we investigate whether the two main consumer confidence indicators available for Sweden – that of the National Institute of Economic Research and that of the European Commission – can nowcast Swedish household consumption expenditure. In a simulated out-of sample nowcast exercise, we find that the consumer confidence indicator of the National Institute of Economic Research appears most useful for this purpose. The root mean square error of the nowcast from the model employing this indicator is the lowest of all the studied models which rely on survey data. The nowcasting performance of the model using the consumer confidence indicator of the European Commission is less impressive; while it outperforms the simplest possible benchmark model, its root mean square error is considerably higher than that of the model relying on the consumer confidence indicator of the National Institute of Economic Research. An implication of our findings is that while the European Commission’s survey programme may have been successful in creating a set of harmonised data for the member countries of the European Union, it is not obvious that the harmonised indicators are the most relevant ones for analysis, nowcasting or forecasting in each country.
在本文中，我们研究了瑞典的两个主要消费者信心指标——国家经济研究所和欧盟委员会的消费者信心指标——是否可以预测瑞典家庭消费支出。在模拟的样本外临近预测练习中，我们发现美国国家经济研究所(National Institute of Economic Research)的消费者信心指标似乎对这一目的最有用。采用该指标的临近预报模型的均方根误差是所有依赖调查数据的模型中最低的。使用欧盟委员会(European Commission)消费者信心指标的模型的临近预测表现不那么令人印象深刻;虽然它优于最简单的基准模型，但其均方根误差远远高于依靠美国国家经济研究所消费者信心指标的模型。我们的发现的一个含义是，虽然欧盟委员会的调查计划可能已经成功地为欧盟成员国创建了一套统一的数据，但统一的指标对于每个国家的分析、临近预测或预测是最相关的，这一点并不明显。
{"title":"Do Swedish Consumer Confidence Indicators Do What They Are Intended to Do","authors":"Bengt Assarsson, Pär Österholm","doi":"10.3790/AEQ.61.4.391","DOIUrl":"https://doi.org/10.3790/AEQ.61.4.391","url":null,"abstract":"In this paper, we investigate whether the two main consumer confidence indicators available for Sweden – that of the National Institute of Economic Research and that of the European Commission – can nowcast Swedish household consumption expenditure. In a simulated out-of sample nowcast exercise, we find that the consumer confidence indicator of the National Institute of Economic Research appears most useful for this purpose. The root mean square error of the nowcast from the model employing this indicator is the lowest of all the studied models which rely on survey data. The nowcasting performance of the model using the consumer confidence indicator of the European Commission is less impressive; while it outperforms the simplest possible benchmark model, its root mean square error is considerably higher than that of the model relying on the consumer confidence indicator of the National Institute of Economic Research. An implication of our findings is that while the European Commission’s survey programme may have been successful in creating a set of harmonised data for the member countries of the European Union, it is not obvious that the harmonised indicators are the most relevant ones for analysis, nowcasting or forecasting in each country.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"391-404"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167409","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 study is unique in using a narrative approach framework to examine whether the very high ratio of indirect to direct taxes in Israel has affected growth in the short term. Indeed, the results suggest that a high ratio of indirect to direct taxes can create a unique environment in which the negative effect of indirect tax increase reaches the negative effect of direct tax increase. The results were stable and robust for both OLS and 2SLS analysis and numerous control variables. Furthermore, the negative effect of indirect tax was achieved in full in the short term, almost exactly as the well-known effect of direct tax documented in many studies. Our interactions analysis suggests that the negative effect of the direct tax is transmitted through both the labor and the capital channels while the negative effect of the indirect tax is transmitted mainly through the capital channel. The results contradict findings on developing countries as well as older results reported in papers on developed countries. Therefore, questions may arise regarding the aims of tax policy in developed countries which usually prefer to raise indirect taxes in order to minimize the negative effects of contractionary fiscal policy.
{"title":"Tax Composition and its Impact on Growth in Israel: A Narrative Approach","authors":"Yaron Zelekha, Hadas Altit, Vered Baram","doi":"10.3790/AEQ.61.3.293","DOIUrl":"https://doi.org/10.3790/AEQ.61.3.293","url":null,"abstract":"This study is unique in using a narrative approach framework to examine whether the very high ratio of indirect to direct taxes in Israel has affected growth in the short term. Indeed, the results suggest that a high ratio of indirect to direct taxes can create a unique environment in which the negative effect of indirect tax increase reaches the negative effect of direct tax increase. The results were stable and robust for both OLS and 2SLS analysis and numerous control variables. Furthermore, the negative effect of indirect tax was achieved in full in the short term, almost exactly as the well-known effect of direct tax documented in many studies. Our interactions analysis suggests that the negative effect of the direct tax is transmitted through both the labor and the capital channels while the negative effect of the indirect tax is transmitted mainly through the capital channel. The results contradict findings on developing countries as well as older results reported in papers on developed countries. Therefore, questions may arise regarding the aims of tax policy in developed countries which usually prefer to raise indirect taxes in order to minimize the negative effects of contractionary fiscal policy.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"293-313"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167599","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}
The determinants of the frequency of Central Bank interventions (purchases and sales) in the Peruvian exchange rate market are analyzed using weekly data for the period from January 2001 to December 2010 using count data models (Poisson, Negative Binomial and Zero Inflated). Findings show that the deviations of the logarithm of the exchange rate with respect to a long term trend, previous week’s interventions (persistency), the Embig spread, the spread between interbank interest rates, and the spread of prime corporate interest rates are important determinants. In terms of the models used, the Zero Inflated models allow a better fit and performance in predicting the number of interventions (purchases and sales).
{"title":"EXPLAINING THE DETERMINANTS OF THE FREQUENCY OF EXCHANGE RATE INTERVENTIONS IN PERU USING COUNT MODELS","authors":"Edgar Neyra, G. Rodríguez","doi":"10.3790/AEQ.61.3.261","DOIUrl":"https://doi.org/10.3790/AEQ.61.3.261","url":null,"abstract":"The determinants of the frequency of Central Bank interventions (purchases and sales) in the Peruvian exchange rate market are analyzed using weekly data for the period from January 2001 to December 2010 using count data models (Poisson, Negative Binomial and Zero Inflated). Findings show that the deviations of the logarithm of the exchange rate with respect to a long term trend, previous week’s interventions (persistency), the Embig spread, the spread between interbank interest rates, and the spread of prime corporate interest rates are important determinants. In terms of the models used, the Zero Inflated models allow a better fit and performance in predicting the number of interventions (purchases and sales).","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"261-292"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70167473","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}
The aim of this study is to investigate the macroeconomic effects of state subsidies for agricultural insurance. From the policy’s point of view, the issue is important as this subsidy is a common and widely applied practice in many countries, though it does not exist in others; so the welfare effects of the subsidy need to be investigated—which investigation is the main contribution of the paper. A possible reason for this subsidy’s existence might be that agricultural insurances by themselves attain only a low penetration rate due to several factors, for example low-risk sensitivity, high premiums, and governments’ ad hoc subsidy policies. Thus, an enabling of risk management is an advantage of the subsidy. According to our results, agricultural insurance subsidizing does not have any significant welfare effect for the user and does not influence the economy’s output significantly; however, it is beneficial for agricultural producers, so one might wish to recommend such a policy if seeking to promote agriculture.
{"title":"Should Governments Subsidize Agricultural Insurances","authors":"G. Regos","doi":"10.3790/AEQ.61.1.65","DOIUrl":"https://doi.org/10.3790/AEQ.61.1.65","url":null,"abstract":"The aim of this study is to investigate the macroeconomic effects of state subsidies for agricultural insurance. From the policy’s point of view, the issue is important as this subsidy is a common and widely applied practice in many countries, though it does not exist in others; so the welfare effects of the subsidy need to be investigated—which investigation is the main contribution of the paper. A possible reason for this subsidy’s existence might be that agricultural insurances by themselves attain only a low penetration rate due to several factors, for example low-risk sensitivity, high premiums, and governments’ ad hoc subsidy policies. Thus, an enabling of risk management is an advantage of the subsidy. According to our results, agricultural insurance subsidizing does not have any significant welfare effect for the user and does not influence the economy’s output significantly; however, it is beneficial for agricultural producers, so one might wish to recommend such a policy if seeking to promote agriculture.","PeriodicalId":36978,"journal":{"name":"Applied Economics Quarterly","volume":"61 1","pages":"65-92"},"PeriodicalIF":0.0,"publicationDate":"2015-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70166934","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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