This paper aims to contribute to a better understanding on how inflation targets are set. For this reason, we first gather evidence from official central bank and government publications and from a questionnaire sent to central banks on how inflation targets are set; we then estimate the determinants of the level of inflation target in 19 inflation targeting countries using unbalanced panel interval regressions (to deal with the issue that targets are typically set as a range rather than as a point). Inflation targets are found to reflect macroeconomic fundamentals. Higher level as well as higher variability of inflation are associated with higher target. The setting of the inflation target is also found to have an important international dimension, as higher world inflation is positively correlated with inflation targets. Rapidly growing countries exhibit higher inflation targets. Our results also suggest that the larger width of inflation target is set in a more volatile macroeconomic environment. We find that central bank credibility is negatively associated with the level of inflation target, suggesting that less credible central banks are likely to recognize the risks related to anchoring inflation expectations at low levels. On the other hand, government party orientation does not matter even in less independent central banks.
{"title":"How are Inflation Targets Set?","authors":"R. Horvath, Jakub Matĕj̊u","doi":"10.2139/ssrn.1699985","DOIUrl":"https://doi.org/10.2139/ssrn.1699985","url":null,"abstract":"This paper aims to contribute to a better understanding on how inflation targets are set. For this reason, we first gather evidence from official central bank and government publications and from a questionnaire sent to central banks on how inflation targets are set; we then estimate the determinants of the level of inflation target in 19 inflation targeting countries using unbalanced panel interval regressions (to deal with the issue that targets are typically set as a range rather than as a point). Inflation targets are found to reflect macroeconomic fundamentals. Higher level as well as higher variability of inflation are associated with higher target. The setting of the inflation target is also found to have an important international dimension, as higher world inflation is positively correlated with inflation targets. Rapidly growing countries exhibit higher inflation targets. Our results also suggest that the larger width of inflation target is set in a more volatile macroeconomic environment. We find that central bank credibility is negatively associated with the level of inflation target, suggesting that less credible central banks are likely to recognize the risks related to anchoring inflation expectations at low levels. On the other hand, government party orientation does not matter even in less independent central banks.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133946979","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 presents a parsimonious model for forecasting and analysing euro area house prices and their interrelations with the macroeconomy. A quarterly vector error correction model is estimated over 1970-2009 using supply and demand forces central to the determination of euro area house prices in equilibrium and their dynamics: housing investment, real disposable income per capita and a mixed maturity measure of the real interest rate. In addition to house price forecasts using the resulting reduced form equation, a structural decomposition of the system is obtained employing a common trends framework of King, Plosser, Stock, and Watson (1991), which allows for the identification and economic interpretation of permanent and transitory shocks. The main results are twofold. First, the reduced form model tracks closely turning points in house prices when examining out-of-sample one- and two- step ahead forecasts. Moreover, the model suggests that euro area housing was overvalued in recent years, implying a period of stagnation to bring housing valuation back in line with its modelled fundamentals. Second, housing demand and financing cost shocks appear to have contributed strongly to the dynamism in euro area house prices over the sample period. While much of the increase appears to reflect a permanent component, a transitory component has also contributed from 2005 onwards. Specification tests suggest a robustness of the small model to alternative specifications, along with validity of the long-run restrictions. JEL Classification: R21, R31, C32
{"title":"Forecasting and Assessing Euro Area House Prices through the Lens of Key Fundamentals","authors":"L. Gattini, P. Hiebert","doi":"10.2139/ssrn.1679733","DOIUrl":"https://doi.org/10.2139/ssrn.1679733","url":null,"abstract":"This paper presents a parsimonious model for forecasting and analysing euro area house prices and their interrelations with the macroeconomy. A quarterly vector error correction model is estimated over 1970-2009 using supply and demand forces central to the determination of euro area house prices in equilibrium and their dynamics: housing investment, real disposable income per capita and a mixed maturity measure of the real interest rate. In addition to house price forecasts using the resulting reduced form equation, a structural decomposition of the system is obtained employing a common trends framework of King, Plosser, Stock, and Watson (1991), which allows for the identification and economic interpretation of permanent and transitory shocks. The main results are twofold. First, the reduced form model tracks closely turning points in house prices when examining out-of-sample one- and two- step ahead forecasts. Moreover, the model suggests that euro area housing was overvalued in recent years, implying a period of stagnation to bring housing valuation back in line with its modelled fundamentals. Second, housing demand and financing cost shocks appear to have contributed strongly to the dynamism in euro area house prices over the sample period. While much of the increase appears to reflect a permanent component, a transitory component has also contributed from 2005 onwards. Specification tests suggest a robustness of the small model to alternative specifications, along with validity of the long-run restrictions. JEL Classification: R21, R31, C32","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132587128","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 accuracy of macroeconomic forecast depends on various factors, most importantly the mix of analytical methods used by the individual forecasters, the way that their personal experience is shaping their identification strategies, but also their efficiency in translating new information into revised forecasts. In this paper we use a broad sample of forecasts of German GDP and its components to analyze the impact of institutions and information on forecast accuracy. We find that forecast errors are a linear function of the forecast horizon. This result is robust over a variety of different specifications. As better information seems to be the key to achieving better forecasts, approaches for acquiring reliable information early seem to be a good investment. By contrast, the institutional factors tend to be small and statistically insignificant. It has to remain open, whether this is the consequence of the efficiency-enhancing competition among German research institutions or rather the reflection of an abundance of forecast suppliers.
{"title":"Information or Institution? On the Determinants of Forecast Accuracy","authors":"Roland Doehrn, C. Schmidt","doi":"10.2139/SSRN.1707984","DOIUrl":"https://doi.org/10.2139/SSRN.1707984","url":null,"abstract":"The accuracy of macroeconomic forecast depends on various factors, most importantly the mix of analytical methods used by the individual forecasters, the way that their personal experience is shaping their identification strategies, but also their efficiency in translating new information into revised forecasts. In this paper we use a broad sample of forecasts of German GDP and its components to analyze the impact of institutions and information on forecast accuracy. We find that forecast errors are a linear function of the forecast horizon. This result is robust over a variety of different specifications. As better information seems to be the key to achieving better forecasts, approaches for acquiring reliable information early seem to be a good investment. By contrast, the institutional factors tend to be small and statistically insignificant. It has to remain open, whether this is the consequence of the efficiency-enhancing competition among German research institutions or rather the reflection of an abundance of forecast suppliers.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124584811","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 recursive modeling approach and data from the Euro area, the following paper analyzes the counter-cyclicity, stock price volatility is believed to demonstrate with respect to the state of the economy. It further tests whether such interdependence is exploitable for volatility forecasting. The sound contribution of this paper is the extension of the in-sample to an out-of-sample analysis. We deliver robust results that greatly challenge the theory of straight and clear-cut link between stock price variability and the state of the economy on an ex ante and ex post basis. Compared with the forecasting ability of an GJR-GARCH-Model, of the implied and historical volatility, the prediction power of macroeconomic and financial information on stock price volatility is practically deprived by the results presented. These underline the information load already incorporated in market prices and stand in line with the efficient-market hypothesis.
{"title":"Volatility Forecasting and the Business Cycle: Evidence from the European Monetary Union","authors":"Daniel Schwake","doi":"10.2139/ssrn.1832631","DOIUrl":"https://doi.org/10.2139/ssrn.1832631","url":null,"abstract":"Using a recursive modeling approach and data from the Euro area, the following paper analyzes the counter-cyclicity, stock price volatility is believed to demonstrate with respect to the state of the economy. It further tests whether such interdependence is exploitable for volatility forecasting. The sound contribution of this paper is the extension of the in-sample to an out-of-sample analysis. We deliver robust results that greatly challenge the theory of straight and clear-cut link between stock price variability and the state of the economy on an ex ante and ex post basis. Compared with the forecasting ability of an GJR-GARCH-Model, of the implied and historical volatility, the prediction power of macroeconomic and financial information on stock price volatility is practically deprived by the results presented. These underline the information load already incorporated in market prices and stand in line with the efficient-market hypothesis.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122824976","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}
Whether a central bank should share with the public its views about the future evolution of short term interest rates is an unresolved issue. Disclosing this information might allow a more precise control of market expectations and a more effective achievement of the ultimate goals of the monetary authority. Yet, if the public do not understand the conditional nature of this forecast, it could also undermine the credibility of the central bank. We provide new evidence on the effects of this announcement on private expectations about future short term interest rates. The communication of policy intentions tends to be associated with a greater predictability of monetary policy decisions. Moreover, focussing on New Zealand, where the central bank releases interest rate projections, we find that market expectations react significantly and persistently to the unexpected part of such forecasts. Finally it emerges that the predicted component of the changes in these projections is large, suggesting that market operators understand their conditionality.
{"title":"The Announcement of Monetary Policy Intentions","authors":"G. Ferrero, Alessandro Secchi","doi":"10.2139/ssrn.1523254","DOIUrl":"https://doi.org/10.2139/ssrn.1523254","url":null,"abstract":"Whether a central bank should share with the public its views about the future evolution of short term interest rates is an unresolved issue. Disclosing this information might allow a more precise control of market expectations and a more effective achievement of the ultimate goals of the monetary authority. Yet, if the public do not understand the conditional nature of this forecast, it could also undermine the credibility of the central bank. We provide new evidence on the effects of this announcement on private expectations about future short term interest rates. The communication of policy intentions tends to be associated with a greater predictability of monetary policy decisions. Moreover, focussing on New Zealand, where the central bank releases interest rate projections, we find that market expectations react significantly and persistently to the unexpected part of such forecasts. Finally it emerges that the predicted component of the changes in these projections is large, suggesting that market operators understand their conditionality.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122077486","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 proposes a comparative analysis of the main macroeconomic aggregates (both real and credit aggregates), and the monetary policy response during the most severe recessions experienced by the Italian economy. This descriptive study focuses mainly on the last forty years, a period for which there is ample and detailed information available. In particular, the paper contrasts the data on the current deep recession with those in 1974-75 and 1992-93, at the times of the oil crisis and the currency crisis respectively. For a selected list of variables, a comparison is made with the dynamics of the recession of the 1930s.
{"title":"The Main Recessions in Italy: A Retrospective Comparison","authors":"Antonio Bassanetti, Martina Cecioni, G. Zevi","doi":"10.2139/SSRN.1479648","DOIUrl":"https://doi.org/10.2139/SSRN.1479648","url":null,"abstract":"This paper proposes a comparative analysis of the main macroeconomic aggregates (both real and credit aggregates), and the monetary policy response during the most severe recessions experienced by the Italian economy. This descriptive study focuses mainly on the last forty years, a period for which there is ample and detailed information available. In particular, the paper contrasts the data on the current deep recession with those in 1974-75 and 1992-93, at the times of the oil crisis and the currency crisis respectively. For a selected list of variables, a comparison is made with the dynamics of the recession of the 1930s.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114896487","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 report describes the semi-aggregate model (SAM) developed to deliver aggregate projections of social protection expenditures as well as semi-aggregate projections of income sources by age class and gender for a number of European countries (Denmark, France, Germany, Italy, Latvia, Luxembourg, Netherlands, Poland, Spain and United Kingdom) over the horizon 2005 - 2050. The partial equilibrium stance adopted allows both a greater flexibility in the choice of countries and in the building of scenarios, while at the same time offering an easier understanding of the model’s inner mechanisms with respect to general equilibrium modelling. Results for aggregate projections are presented, including various sensitivity scenarios devoted at analysing the role of theoretical replacement rates and employment rates – such as the one necessary to fulfil the Lisbon targets – on public pensions expenditures.
{"title":"A Semi-Aggregate Model for Social Expenditure Projections","authors":"P. Ferraresi, C. Monticone","doi":"10.2139/ssrn.2033644","DOIUrl":"https://doi.org/10.2139/ssrn.2033644","url":null,"abstract":"This report describes the semi-aggregate model (SAM) developed to deliver aggregate projections of social protection expenditures as well as semi-aggregate projections of income sources by age class and gender for a number of European countries (Denmark, France, Germany, Italy, Latvia, Luxembourg, Netherlands, Poland, Spain and United Kingdom) over the horizon 2005 - 2050. The partial equilibrium stance adopted allows both a greater flexibility in the choice of countries and in the building of scenarios, while at the same time offering an easier understanding of the model’s inner mechanisms with respect to general equilibrium modelling. Results for aggregate projections are presented, including various sensitivity scenarios devoted at analysing the role of theoretical replacement rates and employment rates – such as the one necessary to fulfil the Lisbon targets – on public pensions expenditures.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123783892","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 derives forecasts for euro area real GDP growth based on a bottom up approach from the production side. That is, GDP is forecast via the forecasts of value added across the different branches of activity, which is quite new in the literature. Linear regression models in the form of bridge equations are applied. In these models earlier available monthly indicators are used to bridge the gap of missing GDP data. The process of selecting the best performing equations is accomplished as a pseudo real time forecasting exercise, i.e. due account is taken of the pattern of available monthly variables over the forecast cycle. Moreover, by applying a very systematic procedure the best performing equations are selected from a pool of thousands of test bridge equations. Our modelling approach, finally, includes a further novelty which should be of particular interest to practitioners. In practice, forecasts for a particular quarter of GDP generally spread over a prolonged period of several months. We explore whether over this forecast cycle, where GDP is repeatedly forecast, the same set of equations or different ones should be used. Changing the set of bridge equations over the forecast cycle could be superior to keeping the same set of equations, as the relative merit of the included monthly indictors may shift over time owing to differences in their data characteristics. Overall, the models derived in this forecast exercise clearly outperform the benchmark models. The variables selected in the best equations for different situations over the forecast cycle vary substantially and the achieved results confirm the conjecture that allowing the variables in the bridge equations to differ over the forecast cycle can lead to substantial improvements in the forecast accuracy. JEL Classification: C22, C52, C53, E27
{"title":"Early Estimates of Euro Area Real GDP Growth: A Bottom Up Approach from the Production Side","authors":"E. Hahn, Frauke Skudelny","doi":"10.2139/ssrn.1304533","DOIUrl":"https://doi.org/10.2139/ssrn.1304533","url":null,"abstract":"This paper derives forecasts for euro area real GDP growth based on a bottom up approach from the production side. That is, GDP is forecast via the forecasts of value added across the different branches of activity, which is quite new in the literature. Linear regression models in the form of bridge equations are applied. In these models earlier available monthly indicators are used to bridge the gap of missing GDP data. The process of selecting the best performing equations is accomplished as a pseudo real time forecasting exercise, i.e. due account is taken of the pattern of available monthly variables over the forecast cycle. Moreover, by applying a very systematic procedure the best performing equations are selected from a pool of thousands of test bridge equations. Our modelling approach, finally, includes a further novelty which should be of particular interest to practitioners. In practice, forecasts for a particular quarter of GDP generally spread over a prolonged period of several months. We explore whether over this forecast cycle, where GDP is repeatedly forecast, the same set of equations or different ones should be used. Changing the set of bridge equations over the forecast cycle could be superior to keeping the same set of equations, as the relative merit of the included monthly indictors may shift over time owing to differences in their data characteristics. Overall, the models derived in this forecast exercise clearly outperform the benchmark models. The variables selected in the best equations for different situations over the forecast cycle vary substantially and the achieved results confirm the conjecture that allowing the variables in the bridge equations to differ over the forecast cycle can lead to substantial improvements in the forecast accuracy. JEL Classification: C22, C52, C53, E27","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117027335","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 a New Keynesian model with asymmetric information we show that publication of macroeconomic projections and of the future interest rate path by the central bank can improve macroeconomic outcomes. However, the gains from publishing interest rate paths are small relative to those from publishing macroeconomic projections. Given that most inflation targeting central banks are already publishing macroeconomic projections this means that most gains from increasing transparency in this area may already have been reaped. This, together with the potential costs, may explain the relative reluctance of central banks to publish interest rate paths.
{"title":"The Relativity Theory Revisited: Is Publishing Interest Rate Forecasts Really so Valuable?","authors":"M. Brzoza‐Brzezina, A. Kot","doi":"10.2139/ssrn.1752917","DOIUrl":"https://doi.org/10.2139/ssrn.1752917","url":null,"abstract":"In a New Keynesian model with asymmetric information we show that publication of macroeconomic projections and of the future interest rate path by the central bank can improve macroeconomic outcomes. However, the gains from publishing interest rate paths are small relative to those from publishing macroeconomic projections. Given that most inflation targeting central banks are already publishing macroeconomic projections this means that most gains from increasing transparency in this area may already have been reaped. This, together with the potential costs, may explain the relative reluctance of central banks to publish interest rate paths.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125345726","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 prices of futures contracts on short-term interest rates are commonly used by central banks to gauge market expectations concerning monetary policy decisions. Excess returns - the difference between futures rates and the realized rates - are positive, on average, and statistically significant, both in the euro area and in the United States. We find that these biases are significantly related to the business cycle only in the United States. Moreover, the sign and the significance of the estimated relationships with business cycle indicators are unstable over time. Breaking the excess returns down into risk premium and forecast error components, we find that risk premia are counter-cyclical in both areas. On the contrary, ex-post prediction errors, which represent the greater part of excess returns at longer horizons in both areas, are correlated with the business cycle (negatively) only in the United States.
{"title":"Short-Term Interest Rate Futures as Monetary Policy Forecasts","authors":"G. Ferrero, A. Nobili","doi":"10.2139/ssrn.1160197","DOIUrl":"https://doi.org/10.2139/ssrn.1160197","url":null,"abstract":"The prices of futures contracts on short-term interest rates are commonly used by central banks to gauge market expectations concerning monetary policy decisions. Excess returns - the difference between futures rates and the realized rates - are positive, on average, and statistically significant, both in the euro area and in the United States. We find that these biases are significantly related to the business cycle only in the United States. Moreover, the sign and the significance of the estimated relationships with business cycle indicators are unstable over time. Breaking the excess returns down into risk premium and forecast error components, we find that risk premia are counter-cyclical in both areas. On the contrary, ex-post prediction errors, which represent the greater part of excess returns at longer horizons in both areas, are correlated with the business cycle (negatively) only in the United States.","PeriodicalId":108782,"journal":{"name":"ERN: Outlooks & Forecasting (Topic)","volume":"1 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":"129851096","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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