One of the main conclusions of Reinhart and Rogoff’s study of sovereign debt crises, highlighted in its title This Time is Different, is that markets for sovereign debt are prone to manic mood swings. When things go well for an extended period, lenders tend to underestimate risks of crisis. They are too short-sighted even to anticipate their own vulnerability to self-fulfilling panic. This paper shows that rational learning about unstable risks can explain most of these phenomena, even when perceptions don’t affect the underlying default risks. Between the relative infrequency of default and the small number of relevant comparators, sovereign debt markets are bound to make rational learners unusually sensitive to recent news. The resulting “rational myopia” makes both confidence and lack of confidence fickle. This can be useful from a policy perspective since it speeds recovery after crisis. However, one bad surprise can deflate it. Simulations show striking understatement of risk on the eve of default. Hence our analysis supports Reinhart and Rogoff’s warning (2009, xxv) that “excessive debt accumulation […] often poses greater system risks than it seems during a boom”. Indeed, it implicitly calls for extra vigilance by policymakers, to help check what lenders almost surely won’t.
{"title":"Why is Confidence in Sovereign Debt Fickle?","authors":"Kent Osband","doi":"10.2139/ssrn.3657641","DOIUrl":"https://doi.org/10.2139/ssrn.3657641","url":null,"abstract":"One of the main conclusions of Reinhart and Rogoff’s study of sovereign debt crises, highlighted in its title This Time is Different, is that markets for sovereign debt are prone to manic mood swings. When things go well for an extended period, lenders tend to underestimate risks of crisis. They are too short-sighted even to anticipate their own vulnerability to self-fulfilling panic. \u0000 \u0000This paper shows that rational learning about unstable risks can explain most of these phenomena, even when perceptions don’t affect the underlying default risks. Between the relative infrequency of default and the small number of relevant comparators, sovereign debt markets are bound to make rational learners unusually sensitive to recent news. The resulting “rational myopia” makes both confidence and lack of confidence fickle. This can be useful from a policy perspective since it speeds recovery after crisis. However, one bad surprise can deflate it. \u0000 \u0000Simulations show striking understatement of risk on the eve of default. Hence our analysis supports Reinhart and Rogoff’s warning (2009, xxv) that “excessive debt accumulation […] often poses greater system risks than it seems during a boom”. Indeed, it implicitly calls for extra vigilance by policymakers, to help check what lenders almost surely won’t.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114122356","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 paper is to detect the existence of financial contagion effects in the Eurozone countries during the sovereign debt crisis. To achieve this purpose, the authors will analyse the contagion effects through the event study methodology and simple regression model, investigating how relevant European press releases (since now called news) affected the performance of Credit Default Swap (CDS), which is a widely used type of credit derivative able to protect an investor from the counter-party's inability to repay its debt. In the study the authors will consider the CDS of three European countries, such as Greece, Germany and United Kingdom, which have different economic and monetary conditions between each other. In conclusion, the outputs of the study will highlight that a financial contagion exists among the selected news and the Eurozone countries, Greece and Germany; whereas there is no considerable evidence of contagion on United Kingdom’s CDS.
{"title":"Have Contagion Effects Occurred in the Eurozone During the Sovereign Debt Crisis?","authors":"Nico Asperti, Gabriele Vedovati, Luca Vuerich","doi":"10.2139/ssrn.3609765","DOIUrl":"https://doi.org/10.2139/ssrn.3609765","url":null,"abstract":"The aim of this paper is to detect the existence of financial contagion effects in the Eurozone countries during the sovereign debt crisis. \u0000 \u0000To achieve this purpose, the authors will analyse the contagion effects through the event study methodology and simple regression model, investigating how relevant European press releases (since now called news) affected the performance of Credit Default Swap (CDS), which is a widely used type of credit derivative able to protect an investor from the counter-party's inability to repay its debt. \u0000 \u0000In the study the authors will consider the CDS of three European countries, such as Greece, Germany and United Kingdom, which have different economic and monetary conditions between each other. \u0000 \u0000In conclusion, the outputs of the study will highlight that a financial contagion exists among the selected news and the Eurozone countries, Greece and Germany; whereas there is no considerable evidence of contagion on United Kingdom’s CDS.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123952543","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}
By using a model incorporating a crisis risk triggered by the accumulation of government debt, we provide a new perspective to explain the driving forces behind secular stagnation associated with a persistent decrease in interest rates. According to the model, the fear of the imposition of a large-scale capital levy in the face of a crisis helps explain Japans decades of persistent stagnation by almost one quarter. As government debt accumulates, not only the level but also the growth rate of output declines persistently, while the government bond yield decreases. We then discuss the possible mechanisms that induce people to share the expectation of a capital levy at the time of a government debt crisis from the historical, theoretical, and political points of view. The model also shows that a permanent increase in consumption tax, which prevents a government debt crisis from occurring, increases social welfare.
{"title":"Secular Stagnation and Low Interest Rates Under the Fear of a Government Debt Crisis","authors":"K. Kobayashi, Kōzō Ueda","doi":"10.2139/ssrn.3583298","DOIUrl":"https://doi.org/10.2139/ssrn.3583298","url":null,"abstract":"By using a model incorporating a crisis risk triggered by the accumulation of government debt, we provide a new perspective to explain the driving forces behind secular stagnation associated with a persistent decrease in interest rates. According to the model, the fear of the imposition of a large-scale capital levy in the face of a crisis helps explain Japans decades of persistent stagnation by almost one quarter. As government debt accumulates, not only the level but also the growth rate of output declines persistently, while the government bond yield decreases. We then discuss the possible mechanisms that induce people to share the expectation of a capital levy at the time of a government debt crisis from the historical, theoretical, and political points of view. The model also shows that a permanent increase in consumption tax, which prevents a government debt crisis from occurring, increases social welfare.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"123 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124645050","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 paper summarizes the literature of the explanations of the European debt crisis. We mainly use literature which was published after the financial crisis 2007/08. Many papers were written about the topic, but there is no clear overview about the different EMU critique. This paper tries to fill this gap. The discussions about advantages and disadvantages started at the end of the 1980s, but they intensified during and after the debt crisis. We classified the literature into non-European and European Economic Monetary Union (EMU) critique. Within the non-European literature especially US economists are relevant who referred to the issue of Optimal Currency Area (OCA). Europe did not fulfil the OCA criteria in their view. The European critique can be divided into ordoliberal, Post-Keynesian and heterodox thoughts. Most relevant for politics is still the ordo liberal EMU critique.
{"title":"Literature Review: Critique of European Monetary Union","authors":"C. Zipper, G. Lechner","doi":"10.2139/ssrn.3383916","DOIUrl":"https://doi.org/10.2139/ssrn.3383916","url":null,"abstract":"The paper summarizes the literature of the explanations of the European debt crisis. We mainly use literature which was published after the financial crisis 2007/08. Many papers were written about the topic, but there is no clear overview about the different EMU critique. This paper tries to fill this gap. The discussions about advantages and disadvantages started at the end of the 1980s, but they intensified during and after the debt crisis. We classified the literature into non-European and European Economic Monetary Union (EMU) critique. Within the non-European literature especially US economists are relevant who referred to the issue of Optimal Currency Area (OCA). Europe did not fulfil the OCA criteria in their view. The European critique can be divided into ordoliberal, Post-Keynesian and heterodox thoughts. Most relevant for politics is still the ordo liberal EMU critique.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131022232","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}
China is Venezuela’s largest bilateral lender as well as a source of diplomatic support. Yet for half a decade Beijing has been steadily unwinding its financial ties with the struggling South American nation. In this article, we demonstrate how China has been ensnarled in a creditor trap in Venezuela. For years, China lent to Venezuela with few policy conditions, securing their lending with loan-for-oil deals and wagering that Venezuela’s oil production capacity was a sufficient guarantee for debt repayment. However, under the shaky leadership of Nicolás Maduro, Venezuela’s economic and political dysfunction has grown at the same time that Chinese confidence in the Bolivarian nation appears to have plummeted. China’s recent lending has been defensive, providing some temporary debt relief to Venezuela to protect Beijing’s considerable financial commitments in the country. At the same time, the Asian giant has signaled its willingness to work with opposition leaders. What does the future hold for China-Venezuela relations, in both economic and political terms?
{"title":"China-Venezuelan Economic Relations: Hedging Venezuelan Bets with Chinese Characteristics","authors":"S. Kaplan, M. Penfold","doi":"10.2139/ssrn.3459035","DOIUrl":"https://doi.org/10.2139/ssrn.3459035","url":null,"abstract":"China is Venezuela’s largest bilateral lender as well as a source of diplomatic support. Yet for half a decade Beijing has been steadily unwinding its financial ties with the struggling South American nation. In this article, we demonstrate how China has been ensnarled in a creditor trap in Venezuela. For years, China lent to Venezuela with few policy conditions, securing their lending with loan-for-oil deals and wagering that Venezuela’s oil production capacity was a sufficient guarantee for debt repayment. However, under the shaky leadership of Nicolás Maduro, Venezuela’s economic and political dysfunction has grown at the same time that Chinese confidence in the Bolivarian nation appears to have plummeted. China’s recent lending has been defensive, providing some temporary debt relief to Venezuela to protect Beijing’s considerable financial commitments in the country. At the same time, the Asian giant has signaled its willingness to work with opposition leaders. What does the future hold for China-Venezuela relations, in both economic and political terms?","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116765776","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}
Forecasting the economic policy uncertainty in Europe is of paramount importance given the on-going debt crisis and the Brexit vote. This paper evaluates monthly out-of-sample economic policy uncertainty index forecasts and examines whether ultra-high frequency information from asset market volatilities and global economic policy uncertainty can improve the forecasts relatively to the no-change forecast. The results show that the global economic policy uncertainty provides the highest predictive gains, followed by the European and US stock market volatilities. The results hold true even when we consider the directional accuracy.
{"title":"Forecasting European Economic Policy Uncertainty","authors":"Stavros Degiannakis, G. Filis","doi":"10.1111/sjpe.12174","DOIUrl":"https://doi.org/10.1111/sjpe.12174","url":null,"abstract":"Forecasting the economic policy uncertainty in Europe is of paramount importance given the on-going debt crisis and the Brexit vote. This paper evaluates monthly out-of-sample economic policy uncertainty index forecasts and examines whether ultra-high frequency information from asset market volatilities and global economic policy uncertainty can improve the forecasts relatively to the no-change forecast. The results show that the global economic policy uncertainty provides the highest predictive gains, followed by the European and US stock market volatilities. The results hold true even when we consider the directional accuracy.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132240263","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 a canonical sovereign default model from Arellano (2008) for Argentina via maximum simulated likelihood estimation to understand how well it performs in terms of predicting default events. The estimated model accounts for the overall default patterns of Argentina and closely matches the default data. Out-of-sample forecasting shows that the model performs better than a logit model in predicting the onset of default events. In terms of the business cycle statistics, the findings of the model are consistent with the data and Arellano (2008), with some caveats.
{"title":"Model-Based Estimation of Sovereign Default","authors":"I. Gumus, Junko Koeda","doi":"10.2139/ssrn.3056539","DOIUrl":"https://doi.org/10.2139/ssrn.3056539","url":null,"abstract":"We estimate a canonical sovereign default model from Arellano (2008) for Argentina via maximum simulated likelihood estimation to understand how well it performs in terms of predicting default events. The estimated model accounts for the overall default patterns of Argentina and closely matches the default data. Out-of-sample forecasting shows that the model performs better than a logit model in predicting the onset of default events. In terms of the business cycle statistics, the findings of the model are consistent with the data and Arellano (2008), with some caveats.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131557490","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}
European banks have been criticized for holding excessive domestic government debt during economic downturns, which may have intensified the diabolic loop between sovereign and bank credit risks. By using a novel bank-level dataset covering the entire timeline of the Eurozone crisis, I first re-confirm that the crisis led to the reallocation of sovereign debt from foreign to domestic banks. This reallocation was only visible for banks as opposed to other domestic private agents and it cannot be explained by the banks' risk-shifting tendency. In contrast to the recent literature focusing only on sovereign debt, I show that banks' private sector exposures were (at least) equally affected by a rise in home bias. Finally, consistent with these patterns, I propose a new debt reallocation channel based on informational frictions and show that informationally closer foreign banks increase their relative exposures when sovereign risk rises. The effect of informational closeness is economically meaningful and robust to the use of different information measures and controls for alternative channels of sovereign debt reallocation.
{"title":"Domestic Banks as Lightning Rods? Home Bias and Information During Eurozone Crisis","authors":"O. Saka","doi":"10.2139/ssrn.2865247","DOIUrl":"https://doi.org/10.2139/ssrn.2865247","url":null,"abstract":"European banks have been criticized for holding excessive domestic government debt during economic downturns, which may have intensified the diabolic loop between sovereign and bank credit risks. By using a novel bank-level dataset covering the entire timeline of the Eurozone crisis, I first re-confirm that the crisis led to the reallocation of sovereign debt from foreign to domestic banks. This reallocation was only visible for banks as opposed to other domestic private agents and it cannot be explained by the banks' risk-shifting tendency. In contrast to the recent literature focusing only on sovereign debt, I show that banks' private sector exposures were (at least) equally affected by a rise in home bias. Finally, consistent with these patterns, I propose a new debt reallocation channel based on informational frictions and show that informationally closer foreign banks increase their relative exposures when sovereign risk rises. The effect of informational closeness is economically meaningful and robust to the use of different information measures and controls for alternative channels of sovereign debt reallocation.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116061569","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}
Carolina Achury, Christos Koulovatianos, J. Tsoukalas
We develop a dynamic recursive model where political and economic decisions interact, to study how excessive debt-GDP ratios affect political sustainability of prudent fiscal policies. Rent seeking groups make political decisions – to cooperate (or not) – on the allocation of fiscal budgets (including rents) and issuance of sovereign debt. A classic commons problem triggers collective fiscal impatience and excessive debt issuing, leading to a vicious circle of high borrowing costs and sovereign default. We analytically characterize debt-GDP thresholds that foster cooperation among rent seeking groups and avoid default. Our analysis and application helps in understanding the politico-economic sustainability of sovereign rescues, emphasizing the need for fiscal targets and possible debt haircuts. We provide a calibrated example that quantifies the threshold debt-GDP ratio at 137%, remarkably close to the target set for private sector involvement in the case of Greece.
{"title":"Political Economics of External Sovereign Defaults","authors":"Carolina Achury, Christos Koulovatianos, J. Tsoukalas","doi":"10.2139/ssrn.2631418","DOIUrl":"https://doi.org/10.2139/ssrn.2631418","url":null,"abstract":"We develop a dynamic recursive model where political and economic decisions interact, to study how excessive debt-GDP ratios affect political sustainability of prudent fiscal policies. Rent seeking groups make political decisions – to cooperate (or not) – on the allocation of fiscal budgets (including rents) and issuance of sovereign debt. A classic commons problem triggers collective fiscal impatience and excessive debt issuing, leading to a vicious circle of high borrowing costs and sovereign default. We analytically characterize debt-GDP thresholds that foster cooperation among rent seeking groups and avoid default. Our analysis and application helps in understanding the politico-economic sustainability of sovereign rescues, emphasizing the need for fiscal targets and possible debt haircuts. We provide a calibrated example that quantifies the threshold debt-GDP ratio at 137%, remarkably close to the target set for private sector involvement in the case of Greece.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129166901","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 : 2014-09-01DOI: 10.5089/9781498358781.001
S. A. Abbas, Laura Blattner, Mark H.J. De Broeck, Asmaa A ElGanainy, Malin Hu
We examine how the composition of public debt, broken down by currency, maturity, holder profile and marketability, has responded to major debt accumulation and consolidation episodes during 1900-2011. Covering thirteen advanced economies, we focus on debt structure shifts that occurred around the two World Wars and global economic downturns, and the subsequent debt consolidations. Notwithstanding data gaps, we are able to recover some broad common patterns. Episodes of large debt accumulation - essentially, large increases in debt supply - were typically absorbed by increases in short-term, foreign currency-denominated, and banking-system-held debt. However, this pattern did not hold during the debt build-ups starting in the 1980s and 1990s, which were compositionally skewed toward long-term local-currency debt. We attribute this change to higher structural demand for sovereign paper, linked to capital account liberalization in advanced economies, the emergence of a large contractual saving sector, and innovative sovereign debt products. With regard to debt consolidations, we find support for the financial repression-cum-inflation channel for post World War II debt reductions. However, the scope for a repeat of this strategy appears limited unless financial liberalization and globalization were materially rolled back or the current globally agreed monetary policy regime built around price stability abandoned. Neither are significant favorable structural demand shifts, as witnessed in the 1980s and 1990s, likely.
{"title":"Sovereign Debt Composition in Advanced Economies: A Historical Perspective","authors":"S. A. Abbas, Laura Blattner, Mark H.J. De Broeck, Asmaa A ElGanainy, Malin Hu","doi":"10.5089/9781498358781.001","DOIUrl":"https://doi.org/10.5089/9781498358781.001","url":null,"abstract":"We examine how the composition of public debt, broken down by currency, maturity, holder profile and marketability, has responded to major debt accumulation and consolidation episodes during 1900-2011. Covering thirteen advanced economies, we focus on debt structure shifts that occurred around the two World Wars and global economic downturns, and the subsequent debt consolidations. Notwithstanding data gaps, we are able to recover some broad common patterns. Episodes of large debt accumulation - essentially, large increases in debt supply - were typically absorbed by increases in short-term, foreign currency-denominated, and banking-system-held debt. However, this pattern did not hold during the debt build-ups starting in the 1980s and 1990s, which were compositionally skewed toward long-term local-currency debt. We attribute this change to higher structural demand for sovereign paper, linked to capital account liberalization in advanced economies, the emergence of a large contractual saving sector, and innovative sovereign debt products. With regard to debt consolidations, we find support for the financial repression-cum-inflation channel for post World War II debt reductions. However, the scope for a repeat of this strategy appears limited unless financial liberalization and globalization were materially rolled back or the current globally agreed monetary policy regime built around price stability abandoned. Neither are significant favorable structural demand shifts, as witnessed in the 1980s and 1990s, likely.","PeriodicalId":366245,"journal":{"name":"PSN: Debt Crises (Topic)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116924424","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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