There is a large literature on incomplete contracts, but one prominent type of incomplete contract has largely gone unnoticed. An "open price contract" is one in which a buyer commits to purchasing goods from a seller even though the price has not been agreed upon at the time of signing. Open price contracts generally give the seller the right to set prices ex post, and the buyer is then obligated to purchase from the seller at those prices. This gives rise to obvious incentives for short-run opportunistic pricing by the seller, but also obvious disincentives from long-run reputational consequences. In this article, we focus on a specific application where open price contracts are common, discuss why buyers enter into such contracts, and test for opportunistic ex-post pricing by sellers on their locked-in buyers. We find that opportunistic incentives are dominated by long-run reputational incentives and to a surprising degree.
{"title":"Open Price Contracts, Locked-In Buyers, and Opportunism","authors":"M. Noel, Hongjie Qiang","doi":"10.2139/ssrn.3660650","DOIUrl":"https://doi.org/10.2139/ssrn.3660650","url":null,"abstract":"There is a large literature on incomplete contracts, but one prominent type of incomplete contract has largely gone unnoticed. An \"open price contract\" is one in which a buyer commits to purchasing goods from a seller even though the price has not been agreed upon at the time of signing. Open price contracts generally give the seller the right to set prices ex post, and the buyer is then obligated to purchase from the seller at those prices. This gives rise to obvious incentives for short-run opportunistic pricing by the seller, but also obvious disincentives from long-run reputational consequences. In this article, we focus on a specific application where open price contracts are common, discuss why buyers enter into such contracts, and test for opportunistic ex-post pricing by sellers on their locked-in buyers. We find that opportunistic incentives are dominated by long-run reputational incentives and to a surprising degree.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117011525","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}
William Grieser, Charles J. Hadlock, J. LeSage, Morad Zekhnini
We study the role of peer effects in capital structure decisions by exploiting the heterogeneous and intransitive nature of product market networks combined with spatial econometric techniques that account for these features. In contrast to prior work, this approach allows us to provide economically meaningful estimates of the magnitude of the causal role of peer effects in capital structure decisions. Our estimates indicate an initial sensitivity of a firm's leverage choice to peer average leverage on the order of .20, indicating a substantive but moderate level of strategic complementarity in capital structure decisions. Our modeling allows peer effects to vary by a firm's location in the product market network, with more central firms having relatively larger aggregate effects on their set of network peers. Our evidence appears most likely to reflect strategic behavior. Extensions of our modeling framework to related finance questions are also briefly considered.
{"title":"Network Effects in Corporate Financial Policies","authors":"William Grieser, Charles J. Hadlock, J. LeSage, Morad Zekhnini","doi":"10.2139/ssrn.3659634","DOIUrl":"https://doi.org/10.2139/ssrn.3659634","url":null,"abstract":"We study the role of peer effects in capital structure decisions by exploiting the heterogeneous and intransitive nature of product market networks combined with spatial econometric techniques that account for these features. In contrast to prior work, this approach allows us to provide economically meaningful estimates of the magnitude of the causal role of peer effects in capital structure decisions. Our estimates indicate an initial sensitivity of a firm's leverage choice to peer average leverage on the order of .20, indicating a substantive but moderate level of strategic complementarity in capital structure decisions. Our modeling allows peer effects to vary by a firm's location in the product market network, with more central firms having relatively larger aggregate effects on their set of network peers. Our evidence appears most likely to reflect strategic behavior. Extensions of our modeling framework to related finance questions are also briefly considered.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"47 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113975836","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}
Over the past few months, the world has witnessed how COVID-19 pandemic disrupted the supply chain of the textile, apparel and fashion manufacturing (TAFM) industry in various unprecedented ways. As the global textile market is interconnected, this outbreak has a global impact due to travel restrictions and raw materials shortages. This study highlights the imminent impact of COVID-19 on the TAFM industry supply chain, focusing on root-cause analysis and statistical data on consumption of textile goods, both locally and globally. There has not been any academic research on TAFM supply chain disruption. This paper has fulfilled this research gap. Our research is a two-fold study. The first part reviews the overall impact of the pandemic on the TAFM industry and conducts a text analysis on the statements collected from business reports, academic journals, market researchers’ opinions, manufacturers’ statements and business journals, in order to identify the most frequently used terms associated with supply chain disruption. The second part is a case study on a ready-made garment (RMG) industry in Bangladesh, which showed that the supply chain disruption due to COVID-19would increase the production cost. This is alarming for garment manufacturers and exporters, as the worldwide apparel consumption is also projected to reduce during and after the pandemic. Lastly, this study forecasts the takeaways of the TAFM industry from this global pandemic and recommends a mathematical model to tackle any similar situation in future.
{"title":"Impact of COVID-19 on the Textile, Apparel and Fashion Manufacturing Industry Supply Chain: Case Study on a Ready-Made Garment Manufacturing Industry","authors":"Samit Chakraborty, M. Biswas","doi":"10.2139/ssrn.3762220","DOIUrl":"https://doi.org/10.2139/ssrn.3762220","url":null,"abstract":"Over the past few months, the world has witnessed how COVID-19 pandemic disrupted the supply chain of the textile, apparel and fashion manufacturing (TAFM) industry in various unprecedented ways. As the global textile market is interconnected, this outbreak has a global impact due to travel restrictions and raw materials shortages. This study highlights the imminent impact of COVID-19 on the TAFM industry supply chain, focusing on root-cause analysis and statistical data on consumption of textile goods, both locally and globally. There has not been any academic research on TAFM supply chain disruption. This paper has fulfilled this research gap. Our research is a two-fold study. The first part reviews the overall impact of the pandemic on the TAFM industry and conducts a text analysis on the statements collected from business reports, academic journals, market researchers’ opinions, manufacturers’ statements and business journals, in order to identify the most frequently used terms associated with supply chain disruption. The second part is a case study on a ready-made garment (RMG) industry in Bangladesh, which showed that the supply chain disruption due to COVID-19would increase the production cost. This is alarming for garment manufacturers and exporters, as the worldwide apparel consumption is also projected to reduce during and after the pandemic. Lastly, this study forecasts the takeaways of the TAFM industry from this global pandemic and recommends a mathematical model to tackle any similar situation in future.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"362 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122810117","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}
Herbie Huang, Nur Sunar, Jayashankar M. Swaminathan
Problem definition: Customer reviews are essential to online marketplaces. However, reviews typically vary; ratings of a product or service are rarely the same. In many service marketplaces, especially the ones for solar panel installations, supply-side participants are active. That is, a seller must make a proposal to serve each customer. In such marketplaces, it is not clear how (or if) the dispersion in customer reviews affects the seller activity level and number of matches in the marketplace. Our paper examines this by considering both ratings and text reviews. Academic/Practical Relevance: To our knowledge, this is the first paper that empirically studies how the review dispersion affects a seller's activity level and the number of matches in an online marketplace with active sellers. Distinct from literature, we examine the relationship between the review dispersion and supply-side activities in an online service marketplace. Methodology: We collaborated with one of the largest online solar marketplaces in the U.S. that connects potential solar panel adopters with installers. We obtained a unique dataset from the marketplace for 2013 - 2018. We complement this with public datasets. Our analysis uses traditional econometrics methods, a clustering method, and the deep-learning-based natural-language-processing model BERT developed by Google AI. Results: We find that the dispersion in customer reviews has a significant and inverted U-shaped effect on an installer's marketplace activity level. Specifically, the installer's activity level increases with the review dispersion if and only if that dispersion is below a certain threshold. Above that threshold, more dispersion in reviews lowers the installer's activity level. Intuitively, a marketplace operator would favor having more sellers with perfect ratings. In contrast, we identify a significant and inverted U-shaped relationship between the market-level review dispersion and transactions. Managerial Implications: Our findings provide valuable insights to marketplace operators about the implications of review dispersions, and call for innovative platform design.
{"title":"Do Noisy Customer Reviews Discourage Platform Sellers? Empirical Analysis of an Online Solar Marketplace","authors":"Herbie Huang, Nur Sunar, Jayashankar M. Swaminathan","doi":"10.2139/ssrn.3645605","DOIUrl":"https://doi.org/10.2139/ssrn.3645605","url":null,"abstract":"Problem definition: Customer reviews are essential to online marketplaces. However, reviews typically vary; ratings of a product or service are rarely the same. In many service marketplaces, especially the ones for solar panel installations, supply-side participants are active. That is, a seller must make a proposal to serve each customer. In such marketplaces, it is not clear how (or if) the dispersion in customer reviews affects the seller activity level and number of matches in the marketplace. Our paper examines this by considering both ratings and text reviews. \u0000 \u0000Academic/Practical Relevance: To our knowledge, this is the first paper that empirically studies how the review dispersion affects a seller's activity level and the number of matches in an online marketplace with active sellers. Distinct from literature, we examine the relationship between the review dispersion and supply-side activities in an online service marketplace. \u0000 \u0000Methodology: We collaborated with one of the largest online solar marketplaces in the U.S. that connects potential solar panel adopters with installers. We obtained a unique dataset from the marketplace for 2013 - 2018. We complement this with public datasets. Our analysis uses traditional econometrics methods, a clustering method, and the deep-learning-based natural-language-processing model BERT developed by Google AI. \u0000 \u0000Results: We find that the dispersion in customer reviews has a significant and inverted U-shaped effect on an installer's marketplace activity level. Specifically, the installer's activity level increases with the review dispersion if and only if that dispersion is below a certain threshold. Above that threshold, more dispersion in reviews lowers the installer's activity level. Intuitively, a marketplace operator would favor having more sellers with perfect ratings. In contrast, we identify a significant and inverted U-shaped relationship between the market-level review dispersion and transactions. \u0000 \u0000Managerial Implications: Our findings provide valuable insights to marketplace operators about the implications of review dispersions, and call for innovative platform design.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"11 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113973977","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 evaluates the recent literature claiming that the US economy has generally become less competitive causing the US economy to perform poorly and that lax antitrust policy is one important reason for the decline in economic performance. Although there certainly are empirical facts requiring further study, I conclude that the evidence does not support calls for dramatic changes in antitrust policy.
{"title":"Some Observations on Claims That Rising Market Power Is Responsible for US Economy Ills and That Lax Antitrust Is the Villain","authors":"D. Carlton","doi":"10.2139/ssrn.3638500","DOIUrl":"https://doi.org/10.2139/ssrn.3638500","url":null,"abstract":"This paper evaluates the recent literature claiming that the US economy has generally become less competitive causing the US economy to perform poorly and that lax antitrust policy is one important reason for the decline in economic performance. Although there certainly are empirical facts requiring further study, I conclude that the evidence does not support calls for dramatic changes in antitrust policy.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130360196","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 : 2020-06-26DOI: 10.31014/aior.1992.03.02.251
Naome A. Etori, D. Alilah
This paper investigates the influence of knowledge management on organizational performance in the case of U.S. retail firms. The paper is based on secondary data analysis, which was collected through a critical review of the literature. The analysis has shown that knowledge management has a significant impact on the performance of organizations in the case of U.S. retail firms. The study found that, when the management of a firm gives importance to the effective management of knowledge, it ultimately helps to improve the performance of that firm. Knowledge management in an effective way is considered important for ensuring long-term prosperity. Knowledge has become the most effective factor for various knowledge-based embedded elements. This is also referred to as exposed tacit due to mobile employees, and therefore its dissemination and development are considered to be significant in order to achieve sustainable competitiveness.
{"title":"Impact of Knowledge Management on Organizational Performance: A Case of U.S. Retail Firms","authors":"Naome A. Etori, D. Alilah","doi":"10.31014/aior.1992.03.02.251","DOIUrl":"https://doi.org/10.31014/aior.1992.03.02.251","url":null,"abstract":"This paper investigates the influence of knowledge management on organizational performance in the case of U.S. retail firms. The paper is based on secondary data analysis, which was collected through a critical review of the literature. The analysis has shown that knowledge management has a significant impact on the performance of organizations in the case of U.S. retail firms. The study found that, when the management of a firm gives importance to the effective management of knowledge, it ultimately helps to improve the performance of that firm. Knowledge management in an effective way is considered important for ensuring long-term prosperity. Knowledge has become the most effective factor for various knowledge-based embedded elements. This is also referred to as exposed tacit due to mobile employees, and therefore its dissemination and development are considered to be significant in order to achieve sustainable competitiveness.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115178271","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}
FinTech growth raises questions about its competitive advantages vis-a-vis traditional providers, the relative risks of FinTech products, and real economic effects. We study FinTech platform small business lending, yielding new answers that may apply to FinTech more generally. Findings suggest that FinTech tends to replace loans by large/out-of-market banks more than small/in-market banks. This is consistent with FinTech advantages in more efficient processing of hard information, rather than hardening of soft information. Additional results suggest that FinTech loans are relatively risky, but become safer after replacing bank loans. Both FinTech and bank loans are found to benefit the real economy.
{"title":"What is Fueling FinTech Lending? The Role of Banking Market Structure","authors":"T. Balyuk, Allen N. Berger, John Hackney","doi":"10.2139/ssrn.3633907","DOIUrl":"https://doi.org/10.2139/ssrn.3633907","url":null,"abstract":"FinTech growth raises questions about its competitive advantages vis-a-vis traditional providers, the relative risks of FinTech products, and real economic effects. We study FinTech platform small business lending, yielding new answers that may apply to FinTech more generally. Findings suggest that FinTech tends to replace loans by large/out-of-market banks more than small/in-market banks. This is consistent with FinTech advantages in more efficient processing of hard information, rather than hardening of soft information. Additional results suggest that FinTech loans are relatively risky, but become safer after replacing bank loans. Both FinTech and bank loans are found to benefit the real economy.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127180539","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 study the impact of the tournament-like competition in the mutual fund industry by examining the Active Share choices of funds. Funds with relatively poor performance by the end of the third quarter in a calendar year tend to increase their Active Share during the last quarter. The increase in the trailing funds' Active Share is accompanied by an increase in the funds' downside risk exposure. The evidence suggests that the strategic shifts in Active Share we document are not information/skill motivated.
{"title":"Mutual Fund Tournaments and Fund Active Share","authors":"C. W. Li, Ashish Tiwari, Lin Tong","doi":"10.2139/ssrn.3074720","DOIUrl":"https://doi.org/10.2139/ssrn.3074720","url":null,"abstract":"We study the impact of the tournament-like competition in the mutual fund industry by examining the Active Share choices of funds. Funds with relatively poor performance by the end of the third quarter in a calendar year tend to increase their Active Share during the last quarter. The increase in the trailing funds' Active Share is accompanied by an increase in the funds' downside risk exposure. The evidence suggests that the strategic shifts in Active Share we document are not information/skill motivated.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132818844","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 examines the theoretical properties of full-cost transfer prices in multidivisional firms. In our model, divisional managers are responsible for the initial acquisition of productive capacity and the utilization of that capacity in subsequent periods, once operational uncertainty has been resolved. We examine alternative variants of full-cost transfer pricing with the property that the discounted sum of transfer payments is equal to the initial capacity acquisition cost and the present value of all subsequent variable costs of output supplied to a division. Our analysis identifies environments where particular variants of full-cost transfer pricing induce efficiency in both the initial investments and the subsequent output levels. Our findings highlight the need for a proper integration of intracompany pricing rules and divisional control rights over capacity assets. This paper was accepted by Suraj Srinivasan, accounting.
{"title":"Capacity Rights and Full Cost Transfer Pricing","authors":"S. Dutta, S. Reichelstein","doi":"10.1287/MNSC.2019.3477","DOIUrl":"https://doi.org/10.1287/MNSC.2019.3477","url":null,"abstract":"This paper examines the theoretical properties of full-cost transfer prices in multidivisional firms. In our model, divisional managers are responsible for the initial acquisition of productive capacity and the utilization of that capacity in subsequent periods, once operational uncertainty has been resolved. We examine alternative variants of full-cost transfer pricing with the property that the discounted sum of transfer payments is equal to the initial capacity acquisition cost and the present value of all subsequent variable costs of output supplied to a division. Our analysis identifies environments where particular variants of full-cost transfer pricing induce efficiency in both the initial investments and the subsequent output levels. Our findings highlight the need for a proper integration of intracompany pricing rules and divisional control rights over capacity assets. This paper was accepted by Suraj Srinivasan, accounting.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126275950","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}
Roland Königsgruber, Pietro Perotti, Oliver Schinnerl, Fanis Tsoligkas, David Windisch
This study examines how product market competition affects firms’ disclosures of their individual segments’ performance. We explicitly account for different types of product market competition by distinguishing between competitors who are already active in a particular market and potential competitors who are considering entering the market. Arguably, firms that are subject to intensive existing competition have lower incentives to conceal information because they are less likely to exhibit abnormal profitability. By contrast, a high level of potential competition constitutes a threat to profitability and hence provides incentives to conceal segment performance. In line with these proprietary cost arguments, we find that potential competition is negatively associated with the disclosure of cross-segment differences in performance, whereas existing competition is positively associated with the disclosure of cross-segment differences in performance. Our results remain robust to a number of sensitivity tests.
{"title":"Product Market Competition and Firms’ Disclosure of Cross-Segment Differences in Performance","authors":"Roland Königsgruber, Pietro Perotti, Oliver Schinnerl, Fanis Tsoligkas, David Windisch","doi":"10.2139/ssrn.3600763","DOIUrl":"https://doi.org/10.2139/ssrn.3600763","url":null,"abstract":"This study examines how product market competition affects firms’ disclosures of their individual segments’ performance. We explicitly account for different types of product market competition by distinguishing between competitors who are already active in a particular market and potential competitors who are considering entering the market. Arguably, firms that are subject to intensive existing competition have lower incentives to conceal information because they are less likely to exhibit abnormal profitability. By contrast, a high level of potential competition constitutes a threat to profitability and hence provides incentives to conceal segment performance. In line with these proprietary cost arguments, we find that potential competition is negatively associated with the disclosure of cross-segment differences in performance, whereas existing competition is positively associated with the disclosure of cross-segment differences in performance. Our results remain robust to a number of sensitivity tests.","PeriodicalId":430354,"journal":{"name":"IO: Empirical Studies of Firms & Markets eJournal","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126377737","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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