This paper provides evidence of habit persistence in household consumption choices. I find that the strength of external habit, captured by the fraction of the consumption of the reference group that enters the utility function, is 0.290, and the strength of internal habit, represented by household past consumption, is 0.503. The results are robust to controlling for various measures of economic activity, tests for the presence of aggregate shocks, liquidity constraints, precautionary saving motives, and learning. Aggregation of the Euler equations as a weighted average of individual marginal rates of substitution accounts for heterogeneity and market incompleteness and preserves the results.
{"title":"Habit Formation and Keeping Up with the Joneses: Evidence from Micro Data","authors":"Enrichetta Ravina","doi":"10.2139/ssrn.928248","DOIUrl":"https://doi.org/10.2139/ssrn.928248","url":null,"abstract":"This paper provides evidence of habit persistence in household consumption choices. I find that the strength of external habit, captured by the fraction of the consumption of the reference group that enters the utility function, is 0.290, and the strength of internal habit, represented by household past consumption, is 0.503. The results are robust to controlling for various measures of economic activity, tests for the presence of aggregate shocks, liquidity constraints, precautionary saving motives, and learning. Aggregation of the Euler equations as a weighted average of individual marginal rates of substitution accounts for heterogeneity and market incompleteness and preserves the results.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"308 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122113750","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 describes a dynamic stochastic general equilibrium model featuring a fraction of non-Ricardian agents in order to estimate the effects of fiscal policy in the Euro area. The model takes into account distortionary taxation on labor and capital income and on consumption, while expenditures are broken down into purchases of goods and services, compensation of public employees and transfers to households. A newly computed quarterly data set of fiscal variables is used. Our results point to the prevalence of mild Keynesian effects of public expenditures. In particular, although innovations in fiscal policy variables tend to be rather persistent, government purchases of goods and services and compensations for public employees have small and short-lived expansionary effects on private consumption, while innovations in transfers to households show a slightly more sizeable and lasting effect. The effects are more significant on the revenue side: decreases in labor income and consumption tax rates have sizeable effects on consumption and output, while a reduction in capital income tax favors investment and output in the medium run. Finally our estimates suggest that fiscal policy variables contribute little to the cyclical variability of the main macro variables.
{"title":"The General Equilibrium Effects of Fiscal Policy: Estimates for the Euro Area","authors":"L. Forni, Libero Monteforte, L. Sessa","doi":"10.2139/ssrn.1075266","DOIUrl":"https://doi.org/10.2139/ssrn.1075266","url":null,"abstract":"This paper describes a dynamic stochastic general equilibrium model featuring a fraction of non-Ricardian agents in order to estimate the effects of fiscal policy in the Euro area. The model takes into account distortionary taxation on labor and capital income and on consumption, while expenditures are broken down into purchases of goods and services, compensation of public employees and transfers to households. A newly computed quarterly data set of fiscal variables is used. Our results point to the prevalence of mild Keynesian effects of public expenditures. In particular, although innovations in fiscal policy variables tend to be rather persistent, government purchases of goods and services and compensations for public employees have small and short-lived expansionary effects on private consumption, while innovations in transfers to households show a slightly more sizeable and lasting effect. The effects are more significant on the revenue side: decreases in labor income and consumption tax rates have sizeable effects on consumption and output, while a reduction in capital income tax favors investment and output in the medium run. Finally our estimates suggest that fiscal policy variables contribute little to the cyclical variability of the main macro variables.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114510323","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 examine the role of off-path "superstitions" in macro-economics, and show how a false belief about off-path play is the key element underlying both the Lucas Critique and the game-theoretic concept of self-confirming equilibrium. However, the impact of false beliefs in these two cases is different: In the Lucas case, a policy maker's incorrect beliefs about off-path play can lead to the adoption of mistaken policy innovation. However, the consequences of such an innovation provide evidence that the belief that motivated them was wrong. In contrast, play may never escape an undesirable self-confirming equilibrium, as the action implied by the mistaken belief does not generate data that contradicts it; escape from the self-confirming equilibrium requires that players do a sufficient amount of experimentation with off-path actions.
{"title":"Self-Confirming Equilibrium and the Lucas Critique","authors":"D. Fudenberg, D. Levine","doi":"10.2139/ssrn.1030298","DOIUrl":"https://doi.org/10.2139/ssrn.1030298","url":null,"abstract":"We examine the role of off-path \"superstitions\" in macro-economics, and show how a false belief about off-path play is the key element underlying both the Lucas Critique and the game-theoretic concept of self-confirming equilibrium. However, the impact of false beliefs in these two cases is different: In the Lucas case, a policy maker's incorrect beliefs about off-path play can lead to the adoption of mistaken policy innovation. However, the consequences of such an innovation provide evidence that the belief that motivated them was wrong. In contrast, play may never escape an undesirable self-confirming equilibrium, as the action implied by the mistaken belief does not generate data that contradicts it; escape from the self-confirming equilibrium requires that players do a sufficient amount of experimentation with off-path actions.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124229112","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 : 2007-11-01DOI: 10.1111/j.1467-9701.2007.01076.x
Sandra Poncet, Olena Havrylchyk
This paper tests the significance of FDI as a way to alleviate credit constraints. Incoming foreign investment provides additional sources of capital. Specifically in the Chinese case, enterprises may look for foreign investors, being constrained in their activity due to distortions in the state-dominated system. First, the Chinese financial system allocates resources to the least efficient firms - state-owned enterprises - while denying the same resources to Chinese private enterprises, forcing them to look for a foreign investor. Second, the inefficient system of state investment planning leads to mismanagement of public enterprises, increasing 'insolvency-induced FDI'. We propose to analyse determinants of FDI in Chinese provinces to test the above hypotheses. We control for traditional determinants of FDI such as market access, labour costs, productivity, infrastructure, reform advances and banking sector size in order to assess the impact of inter-provincial heterogeneity in terms of the access that private enterprises have to credit and the distortive management in state-owned firms. Copyright 2007 The Authors Journal compilation 2007 Blackwell Publishing Ltd .
{"title":"Foreign Direct Investment in China: Reward or Remedy?","authors":"Sandra Poncet, Olena Havrylchyk","doi":"10.1111/j.1467-9701.2007.01076.x","DOIUrl":"https://doi.org/10.1111/j.1467-9701.2007.01076.x","url":null,"abstract":"This paper tests the significance of FDI as a way to alleviate credit constraints. Incoming foreign investment provides additional sources of capital. Specifically in the Chinese case, enterprises may look for foreign investors, being constrained in their activity due to distortions in the state-dominated system. First, the Chinese financial system allocates resources to the least efficient firms - state-owned enterprises - while denying the same resources to Chinese private enterprises, forcing them to look for a foreign investor. Second, the inefficient system of state investment planning leads to mismanagement of public enterprises, increasing 'insolvency-induced FDI'. We propose to analyse determinants of FDI in Chinese provinces to test the above hypotheses. We control for traditional determinants of FDI such as market access, labour costs, productivity, infrastructure, reform advances and banking sector size in order to assess the impact of inter-provincial heterogeneity in terms of the access that private enterprises have to credit and the distortive management in state-owned firms. Copyright 2007 The Authors Journal compilation 2007 Blackwell Publishing Ltd .","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114712606","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 investigate the extent to which start-ups use outside equity, and interpret our results in relation to financial contracting theory. We do so by studying the start-up and founder characteristics that are associated with the use of outside equity financing, using a unique dataset from Norway. Our findings suggest that adverse selection are less of a concern for start-ups than ex-post opportunistic behavior (risk shifting) by the entrepreneur as in Myers (1977) and Ravid & Spiegler (1997). One implication of this finding is that outside equity and debt are complements rather than substitutes, and that an extra unit of equity financing has a multiplicative effect on total financing through releasing additional debt financing. We do not find convincing evidence that the use of outside equity has detrimental effects on entrepreneurial effort, nor that a possible shortage of available outside equity leads to investor monopolization and excessive investor returns. Thus we provide evidence that outside equity provides an important avenue for entrepreneurs to escape liquidity constraints.
{"title":"Start-Up Financing: Outside Equity","authors":"Hans K. Hvide, Aksel Mjøs","doi":"10.2139/ssrn.1023942","DOIUrl":"https://doi.org/10.2139/ssrn.1023942","url":null,"abstract":"We investigate the extent to which start-ups use outside equity, and interpret our results in relation to financial contracting theory. We do so by studying the start-up and founder characteristics that are associated with the use of outside equity financing, using a unique dataset from Norway. Our findings suggest that adverse selection are less of a concern for start-ups than ex-post opportunistic behavior (risk shifting) by the entrepreneur as in Myers (1977) and Ravid & Spiegler (1997). One implication of this finding is that outside equity and debt are complements rather than substitutes, and that an extra unit of equity financing has a multiplicative effect on total financing through releasing additional debt financing. We do not find convincing evidence that the use of outside equity has detrimental effects on entrepreneurial effort, nor that a possible shortage of available outside equity leads to investor monopolization and excessive investor returns. Thus we provide evidence that outside equity provides an important avenue for entrepreneurs to escape liquidity constraints.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123113078","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 consider the problem of pricing path-dependent options on a basket of underlying assets using simulations. As an example we develop our studies using Asian options. Asian options are derivative contracts in which the underlying variable is the average price of given assets sampled over a period of time. Due to this structure, Asian options display a lower volatility and are therefore cheaper than their standard European counterparts. This paper is a survey of some recent enhancements to improve efficiency when pricing Asian options by Monte Carlo simulation in the Black-Scholes model. We analyze the dynamics with constant and time-dependent volatilities of the underlying asset returns. We present a comparison between the precision of the standard Monte Carlo method (MC) and the stratified Latin Hypercube Sampling (LHS). In particular, we discuss the use of low-discrepancy sequences, also known as Quasi-Monte Carlo method (QMC), and a randomized version of these sequences, known as Randomized Quasi Monte Carlo (RQMC). The latter has proven to be a useful variance reduction technique for both problems of up to 20 dimensions and for very high dimensions. Moreover, we present and test a new path generation approach based on a Kronecker product approximation (KPA) in the case of time-dependent volatilities. KPA proves to be a fast generation technique and reduces the computational cost of the simulation procedure.
{"title":"Monte Carlo Methods and Path-Generation Techniques for Pricing Multi-Asset Path-Dependent Options","authors":"P. Sabino","doi":"10.2139/ssrn.1020151","DOIUrl":"https://doi.org/10.2139/ssrn.1020151","url":null,"abstract":"We consider the problem of pricing path-dependent options on a basket of underlying assets using simulations. As an example we develop our studies using Asian options. Asian options are derivative contracts in which the underlying variable is the average price of given assets sampled over a period of time. Due to this structure, Asian options display a lower volatility and are therefore cheaper than their standard European counterparts. This paper is a survey of some recent enhancements to improve efficiency when pricing Asian options by Monte Carlo simulation in the Black-Scholes model. We analyze the dynamics with constant and time-dependent volatilities of the underlying asset returns. We present a comparison between the precision of the standard Monte Carlo method (MC) and the stratified Latin Hypercube Sampling (LHS). In particular, we discuss the use of low-discrepancy sequences, also known as Quasi-Monte Carlo method (QMC), and a randomized version of these sequences, known as Randomized Quasi Monte Carlo (RQMC). The latter has proven to be a useful variance reduction technique for both problems of up to 20 dimensions and for very high dimensions. Moreover, we present and test a new path generation approach based on a Kronecker product approximation (KPA) in the case of time-dependent volatilities. KPA proves to be a fast generation technique and reduces the computational cost of the simulation procedure.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128421284","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 : 2007-10-01DOI: 10.5089/9781451867961.001
Olumuyiwa S. Adedeji, Oral H. Williams
The stance of fiscal policy in CEMAC and WAEMU is strongly influenced by fiscal effort in the previous period. This persistence underscores the risks of a procyclical fiscal policy stance, given these countries' high degree of dependence on primary commodities and exposure to terms of trade shocks. This paper finds that the coefficient of the lagged debt stock was significant and positive, consistent with the theory that higher levels of debt warrant greater fiscal effort. Various measures of economic performance, as captured by economic growth and per capita GDP, openness, and the terms of trade were also found to be important factors in explaining fiscal performance. As fiscal performance seems to be strongly affected by both real GDP growth and terms of trade fluctuations, there appears to be a need to develop supplementary fiscal-related criteria that take into account the influence of output and the terms of trade.
{"title":"Fiscal Reaction Functions in the CFA Zone: An Analytical Perspective","authors":"Olumuyiwa S. Adedeji, Oral H. Williams","doi":"10.5089/9781451867961.001","DOIUrl":"https://doi.org/10.5089/9781451867961.001","url":null,"abstract":"The stance of fiscal policy in CEMAC and WAEMU is strongly influenced by fiscal effort in the previous period. This persistence underscores the risks of a procyclical fiscal policy stance, given these countries' high degree of dependence on primary commodities and exposure to terms of trade shocks. This paper finds that the coefficient of the lagged debt stock was significant and positive, consistent with the theory that higher levels of debt warrant greater fiscal effort. Various measures of economic performance, as captured by economic growth and per capita GDP, openness, and the terms of trade were also found to be important factors in explaining fiscal performance. As fiscal performance seems to be strongly affected by both real GDP growth and terms of trade fluctuations, there appears to be a need to develop supplementary fiscal-related criteria that take into account the influence of output and the terms of trade.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"316 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123305959","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 analyzes the switch from Separate Accounting to Formula Apportionment in a dynamic framework. The model features both purely domestic corporations and a domestic multinational which invests at home and abroad as well as a purely foreign corporation and a foreign multinational which invests in the foreign economy as well as in the domestic country. Using such a framework we can show that since the new FA rules apply only to multinational firms, this will affect the domestic activity of purely domestic or foreign corporations since these stick to SA and thus the marginal product of labour and capital will be different for the two firm types. This in turn will affect the investment incentives and distort capital and labour allocation between the different types of enterprises operating in an economy.
{"title":"From Separate Accounting to Formula Apportionment: Analysis in a Dynamic Framework","authors":"Doina Radulescu","doi":"10.2139/ssrn.1022503","DOIUrl":"https://doi.org/10.2139/ssrn.1022503","url":null,"abstract":"This paper analyzes the switch from Separate Accounting to Formula Apportionment in a dynamic framework. The model features both purely domestic corporations and a domestic multinational which invests at home and abroad as well as a purely foreign corporation and a foreign multinational which invests in the foreign economy as well as in the domestic country. Using such a framework we can show that since the new FA rules apply only to multinational firms, this will affect the domestic activity of purely domestic or foreign corporations since these stick to SA and thus the marginal product of labour and capital will be different for the two firm types. This in turn will affect the investment incentives and distort capital and labour allocation between the different types of enterprises operating in an economy.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128658914","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}
As it evolves around the world, Social Security financed on pay-as-you-go (PAYG) basis increasingly becomes a Ponzi scheme due to aging populations. The main objective of Social Security is to insure seniors against an uncertain life span. However, as the probability of being a net loser rises for coming generations, this objective receives questions with increasing public confusion: how does Social Security affect lifetime wealth? How could one calculate financial terms of Social Security for households in different generations? This paper calculates the aggregate social security wealth (SSW) series for the first time for an emerging country, Turkey. The simulations cover the period between 1970 and 2003 and the results show that the anticipated SSW is the biggest part of household wealth in Turkey and therefore it should not be ignored in economic studies. This paper also analyzes the redistributive characteristics of the system to understand its generational fairness by calculating its implicit internal rate of return and the net gains and losses from participating in the system for representative individuals in different age cohorts. The principal finding is that Social Security in Turkey constitutes significant wealth transfers among different age cohorts.
{"title":"Expected Social Security Wealth Simulations and Generational Fairness of the Turkish PAYG System","authors":"Yigit Aydede","doi":"10.2139/ssrn.1060461","DOIUrl":"https://doi.org/10.2139/ssrn.1060461","url":null,"abstract":"As it evolves around the world, Social Security financed on pay-as-you-go (PAYG) basis increasingly becomes a Ponzi scheme due to aging populations. The main objective of Social Security is to insure seniors against an uncertain life span. However, as the probability of being a net loser rises for coming generations, this objective receives questions with increasing public confusion: how does Social Security affect lifetime wealth? How could one calculate financial terms of Social Security for households in different generations? This paper calculates the aggregate social security wealth (SSW) series for the first time for an emerging country, Turkey. The simulations cover the period between 1970 and 2003 and the results show that the anticipated SSW is the biggest part of household wealth in Turkey and therefore it should not be ignored in economic studies. This paper also analyzes the redistributive characteristics of the system to understand its generational fairness by calculating its implicit internal rate of return and the net gains and losses from participating in the system for representative individuals in different age cohorts. The principal finding is that Social Security in Turkey constitutes significant wealth transfers among different age cohorts.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114331588","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}
Recent evidence on the importance of cross-border equity flows calls for a rethinking of the standard theory of external adjustment. We introduce equity holdings and portfolio choice into an otherwise conventional open-economy dynamic equilibrium model. Our model is simple and admits a closed-form solution regardless of whether financial markets are complete or incomplete. We find that the excessive emphasis put in the literature on solving models with incomplete markets for the sole purpose of obtaining nontrivial implications for the current account is misplaced. We revisit the current debate on the relative importance of the standard vs. the capital-gains-based (or "valuation'') channels of the external adjustment and establish that in our framework they are congruent. Our model's implications are consistent with a number of intriguing stylized facts documented in the recent empirical literature.
{"title":"An Asset-Pricing View of External Adjustment","authors":"A. Pavlova, R. Rigobón","doi":"10.2139/ssrn.1012962","DOIUrl":"https://doi.org/10.2139/ssrn.1012962","url":null,"abstract":"Recent evidence on the importance of cross-border equity flows calls for a rethinking of the standard theory of external adjustment. We introduce equity holdings and portfolio choice into an otherwise conventional open-economy dynamic equilibrium model. Our model is simple and admits a closed-form solution regardless of whether financial markets are complete or incomplete. We find that the excessive emphasis put in the literature on solving models with incomplete markets for the sole purpose of obtaining nontrivial implications for the current account is misplaced. We revisit the current debate on the relative importance of the standard vs. the capital-gains-based (or \"valuation'') channels of the external adjustment and establish that in our framework they are congruent. Our model's implications are consistent with a number of intriguing stylized facts documented in the recent empirical literature.","PeriodicalId":170505,"journal":{"name":"Macroeconomics eJournal","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116421182","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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