Abstract For most active investors treasury bonds (govs) provide diversification and thus reduce the risk of a portfolio. These features of govs become particularly desirable in times of elevated risk which materialize in the form of the flight-to-safety (FTS) phenomenon. The FTS for govs provides a shelter during market turbulence and is exceptionally beneficial for portfolio drawdown risk reduction. However, what if the unsatisfactory expected return from treasuries discourages higher bonds allocations? This research proposes a solution to this problem with Deep Target Volatility Equity-Bond Allocation (DTVEBA) that dynamically allocate portfolios between equity and treasuries. The strategy is driven by a state-of-the-art recurrent neural network (RNN) that predicts next-day market volatility. An analysis conducted over a twelve year out-of-sample period found that with DTVEBA an investor may reduce treasury allocation by two (three) times to get the same Sharpe (Calmar) ratio and overper-forms the S&P500 index by 43% (115%).
对于大多数积极的投资者来说，国库券提供了分散投资，从而降低了投资组合的风险。在风险升高的时候，政府的这些特征变得特别可取，这种风险以“逃向安全”(FTS)现象的形式出现。为政府提供的FTS在市场动荡期间提供了一个避难所，对减少投资组合的风险特别有益。然而，如果美国国债的预期回报不令人满意，导致投资者不愿增持债券，那该怎么办?本文提出了一种深度目标波动率股票-债券配置(Deep Target Volatility equity - bond Allocation, DTVEBA)方法来解决这一问题。该策略由最先进的循环神经网络(RNN)驱动，该网络可以预测第二天的市场波动。一项为期12年的样本外分析发现，使用DTVEBA，投资者可能会将国债配置减少两(三)倍，以获得相同的夏普(卡尔马)比率，并比标准普尔500指数高出43%(115%)。
{"title":"How to fly to safety without overpaying for the ticket","authors":"Tomasz Kaczmarek, Przemysław Grobelny","doi":"10.18559/ebr.2023.2.738","DOIUrl":"https://doi.org/10.18559/ebr.2023.2.738","url":null,"abstract":"Abstract For most active investors treasury bonds (govs) provide diversification and thus reduce the risk of a portfolio. These features of govs become particularly desirable in times of elevated risk which materialize in the form of the flight-to-safety (FTS) phenomenon. The FTS for govs provides a shelter during market turbulence and is exceptionally beneficial for portfolio drawdown risk reduction. However, what if the unsatisfactory expected return from treasuries discourages higher bonds allocations? This research proposes a solution to this problem with Deep Target Volatility Equity-Bond Allocation (DTVEBA) that dynamically allocate portfolios between equity and treasuries. The strategy is driven by a state-of-the-art recurrent neural network (RNN) that predicts next-day market volatility. An analysis conducted over a twelve year out-of-sample period found that with DTVEBA an investor may reduce treasury allocation by two (three) times to get the same Sharpe (Calmar) ratio and overper-forms the S&P500 index by 43% (115%).","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82868917","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}
Abstract This study investigates the role of the country- and firm-level governance practices on the relationship between excess-cash and firm value in ASEAN-5 markets. Using the Generalized Method of Moment models and a sample of 578 firms from 2010 to 2020 the study finds that excess-cash reduces firm value, indicating high agency costs and low firm value. However, excess-cash motivated by managerial ownership, founder CEO, board independence, shareholder rights and creditor rights increase firm value while excess-cash due to managerial entrenchment and CEODuality reduce firm value. In the sub-sample analyses the study finds that entrenched managers and board size play a less effective role in wasting excess-cash in low-excess-cash firms while independent directors play a higher monitoring role in high-excess-cash firms. In addition, governance at the country-level is more effective than at the firm-level in improving the value of excess-cash in large firms. The study offers unique evidence on the relationship between excess-cash and firm value by integrating corporate governance practices at the firm- and country-levels. The research aids practitioners, academics, policymakers and investors in developing the best liquidity policies to enhance business performance.
{"title":"Corporate governance, excess-cash and firm value: Evidence from ASEAN-5","authors":"Tahir Akhtar","doi":"10.18559/ebr.2022.4.3","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.3","url":null,"abstract":"Abstract This study investigates the role of the country- and firm-level governance practices on the relationship between excess-cash and firm value in ASEAN-5 markets. Using the Generalized Method of Moment models and a sample of 578 firms from 2010 to 2020 the study finds that excess-cash reduces firm value, indicating high agency costs and low firm value. However, excess-cash motivated by managerial ownership, founder CEO, board independence, shareholder rights and creditor rights increase firm value while excess-cash due to managerial entrenchment and CEODuality reduce firm value. In the sub-sample analyses the study finds that entrenched managers and board size play a less effective role in wasting excess-cash in low-excess-cash firms while independent directors play a higher monitoring role in high-excess-cash firms. In addition, governance at the country-level is more effective than at the firm-level in improving the value of excess-cash in large firms. The study offers unique evidence on the relationship between excess-cash and firm value by integrating corporate governance practices at the firm- and country-levels. The research aids practitioners, academics, policymakers and investors in developing the best liquidity policies to enhance business performance.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87323950","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}
Abstract The aim of the article is to evaluate the market reaction to the change of listing venue of companies moving from the alternative market to the regulated market of the Warsaw Stock Exchange. To do so, we investigated 71 switches, and their effect on market returns and liquidity. While the transfer itself creates a negative market reaction, the announcement of the transfer of a company and the institutional confirmation by the supervision of the company’s readiness for this transfer resulting from the approval of the prospectus creates positive market reactions. As a result of the transfer of companies there is an improvement in the liquidity of the shares. The empirical findings of the study could assist managers and investors in understanding the impact of stock exchange migration on returns and the liquidity of shares in the shorter and longer term.
{"title":"Stock returns and liquidity after listing switch on the Warsaw Stock Exchange","authors":"Dorota Podedworna-Tarnowska, Daniel Kaszyński","doi":"10.18559/ebr.2022.4.6","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.6","url":null,"abstract":"Abstract The aim of the article is to evaluate the market reaction to the change of listing venue of companies moving from the alternative market to the regulated market of the Warsaw Stock Exchange. To do so, we investigated 71 switches, and their effect on market returns and liquidity. While the transfer itself creates a negative market reaction, the announcement of the transfer of a company and the institutional confirmation by the supervision of the company’s readiness for this transfer resulting from the approval of the prospectus creates positive market reactions. As a result of the transfer of companies there is an improvement in the liquidity of the shares. The empirical findings of the study could assist managers and investors in understanding the impact of stock exchange migration on returns and the liquidity of shares in the shorter and longer term.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79653710","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}
P. L. Angosto-Fernández, Victoria Ferrández-Serrano
Abstract The aim of the paper is to analyse the impact of the new coronavirus on financial markets. The sample comprises returns from 80 countries, across all regions and incomes for the period known as the first wave. By combining event study methodology and time series analysis of new COVID-19 cases it is found that the negative price effect is widespread but unequal across regions. It is also noted that the distribution of the impact is also uneven with a high concentration in the week after the first local case but especially in the weeks around the pandemic declaration. Finally, it has been shown at different levels how the markets most affected by the crisis are not necessarily the most sensitive to the virus.
{"title":"World capital markets facing the first wave of COVID-19: Traditional event study versus sensitivity to new cases","authors":"P. L. Angosto-Fernández, Victoria Ferrández-Serrano","doi":"10.18559/ebr.2022.4.2","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.2","url":null,"abstract":"Abstract The aim of the paper is to analyse the impact of the new coronavirus on financial markets. The sample comprises returns from 80 countries, across all regions and incomes for the period known as the first wave. By combining event study methodology and time series analysis of new COVID-19 cases it is found that the negative price effect is widespread but unequal across regions. It is also noted that the distribution of the impact is also uneven with a high concentration in the week after the first local case but especially in the weeks around the pandemic declaration. Finally, it has been shown at different levels how the markets most affected by the crisis are not necessarily the most sensitive to the virus.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79819526","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}
Abstract Although talent is considered imperative for gaining a competitive advantage, talent management programs’ effectiveness is unknown. It is believed that consensus on a strong theoretical underpinning for identifying talent and its general definition is yet to be achieved among academia and practitioners. This lack of integration and agreement on a single definition among scholars lead to more confusion which inhibits the advancement of talent management scholarship. The notion also requires renewed attention in the post-pandemic era because everything may not go back to normal as pre-pandemic. This study addresses the gap and focuses on reviewing the existing scholarship on talent definitions and its conceptualization in one place. The study also aims to present the potential implications of talent definition on talent management practices. Among the various implications discussed, it is argued that a single approach to talent definition makes the company vulnerable as it is not using the full potential of talent management. Finally, based on this in-depth review, the study will highlight potential critical research areas towards which the scholarship of talent may be extended.
{"title":"Who is talent? Implications of talent definitions for talent management practice","authors":"A. Skuza, Habte G. Woldu, Shawn Alborz","doi":"10.18559/ebr.2022.4.7","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.7","url":null,"abstract":"Abstract Although talent is considered imperative for gaining a competitive advantage, talent management programs’ effectiveness is unknown. It is believed that consensus on a strong theoretical underpinning for identifying talent and its general definition is yet to be achieved among academia and practitioners. This lack of integration and agreement on a single definition among scholars lead to more confusion which inhibits the advancement of talent management scholarship. The notion also requires renewed attention in the post-pandemic era because everything may not go back to normal as pre-pandemic. This study addresses the gap and focuses on reviewing the existing scholarship on talent definitions and its conceptualization in one place. The study also aims to present the potential implications of talent definition on talent management practices. Among the various implications discussed, it is argued that a single approach to talent definition makes the company vulnerable as it is not using the full potential of talent management. Finally, based on this in-depth review, the study will highlight potential critical research areas towards which the scholarship of talent may be extended.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78509470","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}
Abstract This paper analyses the effect of credit on monetary policy responses for different regimes in Turkey. To do so, the Taylor rule augmented with the credit gap is estimated by using a Markov regime switching model from January 2006 to December 2019. The empirical findings identify two regimes: the low- and high-interest rate regimes. The prevalence of the former indicates policy authorities’ growth priorities. Furthermore, differing responses across the regimes reflect that the Central Bank of the Republic of Turkey has an asymmetric policy stance. In the low-interest rate regime, the monetary policy only significantly responds to inflation. In the high-interest rate regime, both inflation and credit have significant positive impacts on interest rate setting. This indicates that credit conditions affected the tightening of the monetary policy stance in Turkey despite the use of macroprudential tools after the global financial crisis.
{"title":"Examining the effect of credit on monetary policy with Markov regime switching: Evidence from Turkey","authors":"A. Ilhan","doi":"10.18559/ebr.2022.4.4","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.4","url":null,"abstract":"Abstract This paper analyses the effect of credit on monetary policy responses for different regimes in Turkey. To do so, the Taylor rule augmented with the credit gap is estimated by using a Markov regime switching model from January 2006 to December 2019. The empirical findings identify two regimes: the low- and high-interest rate regimes. The prevalence of the former indicates policy authorities’ growth priorities. Furthermore, differing responses across the regimes reflect that the Central Bank of the Republic of Turkey has an asymmetric policy stance. In the low-interest rate regime, the monetary policy only significantly responds to inflation. In the high-interest rate regime, both inflation and credit have significant positive impacts on interest rate setting. This indicates that credit conditions affected the tightening of the monetary policy stance in Turkey despite the use of macroprudential tools after the global financial crisis.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81609778","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}
Abstract This study examines the linkages between GVC involvement and wages in Poland given different wage bargaining schemes. The analysis is based on microdata from the European Structure of Earnings Survey for Poland combined with sectoral data from the World Input-Output Database. In particular, two measures of GVC involvement were used: the share of foreign value added (FVA) to export and the measure of traditional offshoring. The institutional settings are represented by the wage bargaining scheme which reflects the level at which the collective pay is agreed. The results show that despite the lack of a significant relationship between the sectoral involvement in GVC and the level of wages in Poland, on average workers covered by the collective pay agreement receive higher wages. Moreover, the wage-GVC nexus is conditioned on the type of pay agreements: the positive wage effect from national agreements is eliminated for a certain range of GVC intensity.
{"title":"Wage determination, Global Value Chains and role played by wage bargaining schemes: The case of Poland","authors":"D. Nikulin, Joanna Wolszczak-Derlacz","doi":"10.18559/ebr.2022.4.5","DOIUrl":"https://doi.org/10.18559/ebr.2022.4.5","url":null,"abstract":"Abstract This study examines the linkages between GVC involvement and wages in Poland given different wage bargaining schemes. The analysis is based on microdata from the European Structure of Earnings Survey for Poland combined with sectoral data from the World Input-Output Database. In particular, two measures of GVC involvement were used: the share of foreign value added (FVA) to export and the measure of traditional offshoring. The institutional settings are represented by the wage bargaining scheme which reflects the level at which the collective pay is agreed. The results show that despite the lack of a significant relationship between the sectoral involvement in GVC and the level of wages in Poland, on average workers covered by the collective pay agreement receive higher wages. Moreover, the wage-GVC nexus is conditioned on the type of pay agreements: the positive wage effect from national agreements is eliminated for a certain range of GVC intensity.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84088116","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}
Abstract The purpose of this paper is to provide the framework to analyze the impact of shocks related to the COVID-19 pandemic on the level of divorce. The model takes into account family/marriage capital with its depreciation, investments in this capital and the costs of divorce. The problem faced by the agent is analyzed and formulas for the optimal division of income between consumption and investments in family capital are derived. Comparative statics is performed by calculating the signs of all derivatives of all variables with respect to all parameters. The analysis shows that a change in economic conditions has the least effect of any factor influenced by COVID-19 in changing the probability of a divorce. To the best of the authors’ knowledge this is the first mathematical model in the literature that covers the issues of the impact of a lock-down on the durability of marriages.
{"title":"Marriage, divorce and coronavirus—theoretical analysis of the influence of COVID-19 on family capital","authors":"Paulina Malaczewska, Maciej Malaczewski","doi":"10.18559/ebr.2022.3.7","DOIUrl":"https://doi.org/10.18559/ebr.2022.3.7","url":null,"abstract":"Abstract The purpose of this paper is to provide the framework to analyze the impact of shocks related to the COVID-19 pandemic on the level of divorce. The model takes into account family/marriage capital with its depreciation, investments in this capital and the costs of divorce. The problem faced by the agent is analyzed and formulas for the optimal division of income between consumption and investments in family capital are derived. Comparative statics is performed by calculating the signs of all derivatives of all variables with respect to all parameters. The analysis shows that a change in economic conditions has the least effect of any factor influenced by COVID-19 in changing the probability of a divorce. To the best of the authors’ knowledge this is the first mathematical model in the literature that covers the issues of the impact of a lock-down on the durability of marriages.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82949875","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}
Abstract The aim of the paper is to evaluate the investment attractiveness of selected energy tokens from the point of view of the effectiveness measures applied to ordinary financial instruments. The authors also classify energy tokens among climate-aligned tokens and digital instruments of green investments financing. In this way, it was possible to compare energy tokens against traditional financial instruments. Furthermore, the authors attempted to investigate the relationship between the formation of returns of the researched energy tokens and the returns on stock and commodity markets. The results of the study indicate the low investment attractiveness of energy tokens compared to investments in stock markets, commodity markets and investments in major cryptocurrencies such as Bitcoin and Ethereum. The research therefore indicates that buyers of energy tokens today should not be driven by investment or speculative motives but rather by a desire to obtain a means of clearing energy trading, or other utility.
{"title":"Energy tokens as digital instruments of financial investment","authors":"Kamilla Marchewka-Bartkowiak, Marcin Wiśniewski","doi":"10.18559/ebr.2022.3.6","DOIUrl":"https://doi.org/10.18559/ebr.2022.3.6","url":null,"abstract":"Abstract The aim of the paper is to evaluate the investment attractiveness of selected energy tokens from the point of view of the effectiveness measures applied to ordinary financial instruments. The authors also classify energy tokens among climate-aligned tokens and digital instruments of green investments financing. In this way, it was possible to compare energy tokens against traditional financial instruments. Furthermore, the authors attempted to investigate the relationship between the formation of returns of the researched energy tokens and the returns on stock and commodity markets. The results of the study indicate the low investment attractiveness of energy tokens compared to investments in stock markets, commodity markets and investments in major cryptocurrencies such as Bitcoin and Ethereum. The research therefore indicates that buyers of energy tokens today should not be driven by investment or speculative motives but rather by a desire to obtain a means of clearing energy trading, or other utility.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75665453","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}
Abstract The Rule of Law serves, under a broadly accepted notion of justice, the enforcement of property rights and a relative predictability of citizen affairs, i.e. it fosters Public Value. However, it is subject to risks that materialise in weakened institutions, uncertainty and transaction costs. The connection between Public Value and the Rule of Law becomes salient when understanding how the latter degenerates at the expense of the former. This article provides two theoretical frameworks that explain the connection between the two concepts, as well as three manifestations of the Rule of Law’s decay. These comprise the excess of legal-formalism, the excess of discretion in enforcement and the instrumentalisation of the law, i.e. when it embodies injustice. Although they vary depending on the legal system, these aspects build a conceptual body that illustrates how contingent legal outcomes affect society, developing Daly’s (2019) concept of democratic decay in the economics and business literature.
{"title":"Absurda lex, sed lex? Public value and the decay of the Rule of Law: A conceptual perspective","authors":"Erick Behar-Villegas","doi":"10.18559/ebr.2022.3.2","DOIUrl":"https://doi.org/10.18559/ebr.2022.3.2","url":null,"abstract":"Abstract The Rule of Law serves, under a broadly accepted notion of justice, the enforcement of property rights and a relative predictability of citizen affairs, i.e. it fosters Public Value. However, it is subject to risks that materialise in weakened institutions, uncertainty and transaction costs. The connection between Public Value and the Rule of Law becomes salient when understanding how the latter degenerates at the expense of the former. This article provides two theoretical frameworks that explain the connection between the two concepts, as well as three manifestations of the Rule of Law’s decay. These comprise the excess of legal-formalism, the excess of discretion in enforcement and the instrumentalisation of the law, i.e. when it embodies injustice. Although they vary depending on the legal system, these aspects build a conceptual body that illustrates how contingent legal outcomes affect society, developing Daly’s (2019) concept of democratic decay in the economics and business literature.","PeriodicalId":41557,"journal":{"name":"Economics and Business Review","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74040872","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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