The UN System of National Accounts (SNA) calculates standard national income (NI) under the condition that owned capital is maintained. Roefie Hueting defined in 1969 environmental functions (state, stock) as the possible uses by humans of the environment. Their actual use (flow) nowadays are also called ecosystem services. Hueting defined in 1986 environmentally sustainable national income (eSNI) (flow) under the condition that the vital environmental functions are maintained for future generations. Then eΔ = NI – eSNI gives the national distance to environmental sustainability. Thus eΔ measures the level of ecosystem services concerning the part that infringes upon environmental sustainability, or the abusive part in the ecosystem services that are provided. This communication aspires at a translation of the terminologies by economist Hueting and ecologists in the research of ecosystem services.
联合国国民经济核算系统(SNA)在保留自有资本的情况下计算标准国民收入(NI)。Roefie Hueting在1969年将环境功能(状态，存量)定义为人类对环境的可能利用。它们的实际用途(流量)现在也被称为生态系统服务。huting在1986年定义了环境可持续国民收入(eSNI)(流量)，前提是为子孙后代维持重要的环境功能。然后eΔ = NI - eSNI给出了国家对环境可持续性的距离。因此，eΔ衡量的是生态系统服务的水平，涉及侵犯环境可持续性的部分，或所提供的生态系统服务中滥用的部分。本交流旨在翻译经济学家huting和生态学家在生态系统服务研究中的术语。
{"title":"National Accounts in the Anthropocene: Hueting’s Environmental Functions and Environmentally Sustainable National Income: Translation and Relevance for Ecosystem Services","authors":"Thomas Colignatus","doi":"10.2139/ssrn.3419402","DOIUrl":"https://doi.org/10.2139/ssrn.3419402","url":null,"abstract":"The UN System of National Accounts (SNA) calculates standard national income (NI) under the condition that owned capital is maintained. Roefie Hueting defined in 1969 environmental functions (state, stock) as the possible uses by humans of the environment. Their actual use (flow) nowadays are also called ecosystem services. Hueting defined in 1986 environmentally sustainable national income (eSNI) (flow) under the condition that the vital environmental functions are maintained for future generations. Then eΔ = NI – eSNI gives the national distance to environmental sustainability. Thus eΔ measures the level of ecosystem services concerning the part that infringes upon environmental sustainability, or the abusive part in the ecosystem services that are provided. This communication aspires at a translation of the terminologies by economist Hueting and ecologists in the research of ecosystem services.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115584272","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 the first detailed and holistic description of the European production network (EPN) and provides different rankings of the most 'systemically important' industries involved in Brexit. Employing techniques of complex networks analysis and Input-Output traditional tools, the study identifies those industries that are key in the complex structure of the UK-EU trade relationships. The method developed would help policy-makers to better understand which tariff would have a more distortive impact, which export sector should be pushed, which imports should be safeguarded. Such information may have foremost importance in the negotiations between the UK and EU. Our findings suggest that Brexit would be not just a problem for the UK, as it is often portrayed, but any form of Brexit could propagate affecting the global production system. Further, by inspecting industries centrality within the EPN, we find that the UK could be less exposed to trade barriers than EU countries.
{"title":"Key Sectors in Input-Output Production Networks: An Application to Brexit","authors":"Raffaele Giammetti, Alberto Russo, M. Gallegati","doi":"10.2139/ssrn.3347545","DOIUrl":"https://doi.org/10.2139/ssrn.3347545","url":null,"abstract":"This paper presents the first detailed and holistic description of the European production network (EPN) and provides different rankings of the most 'systemically important' industries involved in Brexit. Employing techniques of complex networks analysis and Input-Output traditional tools, the study identifies those industries that are key in the complex structure of the UK-EU trade relationships. The method developed would help policy-makers to better understand which tariff would have a more distortive impact, which export sector should be pushed, which imports should be safeguarded. Such information may have foremost importance in the negotiations between the UK and EU. Our findings suggest that Brexit would be not just a problem for the UK, as it is often portrayed, but any form of Brexit could propagate affecting the global production system. Further, by inspecting industries centrality within the EPN, we find that the UK could be less exposed to trade barriers than EU countries.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120938478","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}
Measures devised to quantify value chain position have been used increasingly in recent years. While the constructs underlying these measures are meaningful, this paper identifies an overlooked implementation problem. Proposed algorithms have been applied as though the underlying data represent flows. Implementation data are drawn from modern input-output accounting frameworks that recognize secondary production explicitly. Unadjusted Use matrices are not conventional flows matrices because they do not identify the industries from which commodities originate. We demonstrate logical inconsistencies that arise, provide correct flow matrix formulations for upstreamness and downstreamness measures, and present empirical comparisons of correct and incorrect formulations.
{"title":"Value Chains: Production Upstreamness and Downstreamness Revisited","authors":"P. Aroca, R. Jackson","doi":"10.2139/ssrn.3647496","DOIUrl":"https://doi.org/10.2139/ssrn.3647496","url":null,"abstract":"Measures devised to quantify value chain position have been used increasingly in recent years. While the constructs underlying these measures are meaningful, this paper identifies an overlooked implementation problem. Proposed algorithms have been applied as though the underlying data represent flows. Implementation data are drawn from modern input-output accounting frameworks that recognize secondary production explicitly. Unadjusted Use matrices are not conventional flows matrices because they do not identify the industries from which commodities originate. We demonstrate logical inconsistencies that arise, provide correct flow matrix formulations for upstreamness and downstreamness measures, and present empirical comparisons of correct and incorrect formulations.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"51 19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122213810","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}
M. van den Berg, Ilke Van Beveren, O. Lemmers, Tommy Span, Adam N. Walker
This study assesses the contribution of the Dutch public export credit insurance facility (ECIF) to Dutch GDP and employment. Unlike previous studies, which generally adopt the gravity model of trade, we adopt an input-output approach. The results show that the contribution of economic activity insured by the public ECIF to GDP averages 0.24 percent annually. This concerns value added generated both by exporters and their domestic suppliers in the value chain. The contribution to employment shows an average of 0.27 percent, accumulating to 95,000 jobs (FTE) over 5 years. The estimated contribution of the public ECIF to the Dutch economy should be considered an upper boundary of its true contribution. Therefore, we examine the extent to which the above economic gains would be realized if the facility was unavailable using highly disaggregated trade data. The basic idea is that if certain products are only exported to certain destinations with the aid of the public ECIF, then this suggests 100 percent additionality. The inconclusiveness of our results underlines the difficulties in assessing the degree of additionality.
{"title":"Public Export Credit Insurance in the Netherlands: An Input-Output Approach","authors":"M. van den Berg, Ilke Van Beveren, O. Lemmers, Tommy Span, Adam N. Walker","doi":"10.2139/ssrn.3160976","DOIUrl":"https://doi.org/10.2139/ssrn.3160976","url":null,"abstract":"This study assesses the contribution of the Dutch public export credit insurance facility (ECIF) to Dutch GDP and employment. Unlike previous studies, which generally adopt the gravity model of trade, we adopt an input-output approach. The results show that the contribution of economic activity insured by the public ECIF to GDP averages 0.24 percent annually. This concerns value added generated both by exporters and their domestic suppliers in the value chain. The contribution to employment shows an average of 0.27 percent, accumulating to 95,000 jobs (FTE) over 5 years. The estimated contribution of the public ECIF to the Dutch economy should be considered an upper boundary of its true contribution. Therefore, we examine the extent to which the above economic gains would be realized if the facility was unavailable using highly disaggregated trade data. The basic idea is that if certain products are only exported to certain destinations with the aid of the public ECIF, then this suggests 100 percent additionality. The inconclusiveness of our results underlines the difficulties in assessing the degree of additionality.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129901799","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}
Balázs Kotosz, M. Lukovics, Gabriella Molnár, Bence Zuti
Today, the realization that certain economic units, such as universities or other large tertiary educational institutions have an impact on the economy of their region has gained prominence. There is a growing demand for precise studies on the economic impact of such entities, and the issue has attracted considerable attention in the scientific community. The examination of their economic impact is especially interesting when we compare regions with different levels of development, characterized by a successful international university. The different methods used in the literature render comparisons difficult; therefore, our focus is to recommend a method for investigating universities in different countries. In the absence of regional input-output matrices, a multiplier based approach is suggested for the first and second mission (education and research), while the application of a set of indicators is recommended for the third mission (knowledge transfer-related). There are several substantial problems in assessing the economic impact of universities. First, the definition of impact; second, measuring and estimating first-round expenditures and avoiding double-counting; third, estimating the model parameters (e.g. multipliers); fourth, the quantification of third mission activities. In this paper, we clarify theoretical definitions, resolve some contradictions, and consequently, recommend a feasible method considering the circumstances in Hungary.
{"title":"How to Measure the Local Economic Impact of Universities? Methodological Overview","authors":"Balázs Kotosz, M. Lukovics, Gabriella Molnár, Bence Zuti","doi":"10.15196/rs05201","DOIUrl":"https://doi.org/10.15196/rs05201","url":null,"abstract":"Today, the realization that certain economic units, such as universities or other large tertiary educational institutions have an impact on the economy of their region has gained prominence. There is a growing demand for precise studies on the economic impact of such entities, and the issue has attracted considerable attention in the scientific community. The examination of their economic impact is especially interesting when we compare regions with different levels of development, characterized by a successful international university. The different methods used in the literature render comparisons difficult; therefore, our focus is to recommend a method for investigating universities in different countries. In the absence of regional input-output matrices, a multiplier based approach is suggested for the first and second mission (education and research), while the application of a set of indicators is recommended for the third mission (knowledge transfer-related). There are several substantial problems in assessing the economic impact of universities. First, the definition of impact; second, measuring and estimating first-round expenditures and avoiding double-counting; third, estimating the model parameters (e.g. multipliers); fourth, the quantification of third mission activities. In this paper, we clarify theoretical definitions, resolve some contradictions, and consequently, recommend a feasible method considering the circumstances in Hungary.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114546023","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 an urban economy, the distribution of people and real estate prices depends on the location of the central business district of a city. As distance from the city center increases, both prices and population density diminish, for travel costs increase in terms of time and money. As manufacturing gradually leaves the cities, the importance of consumer amenities as attractors of population to the urban areas increases. The role of a business center is being replaced by the consumer center. In this paper, we identify the location of the consumer center of St. Petersburg - the second largest city in Russia and its former capital. For this purpose using the data from open sources in the Internet regarding the location of many different types of urban amenities, the indices of their spatial density are computed. Using the weights based on coefficients of spatial variation and survey-based weights, the individual indices are aggregated to two general centrality indices. Their unique maxima correspond to the city center of St. Petersburg, which is located on Nevsky prospekt, between Fontanka river and Liteinyi prospekt.
{"title":"Where is the Consumer Center of St. Petersburg?","authors":"K. Kholodilin, I. Krylova, Darya Kryutchenko","doi":"10.2139/ssrn.2970482","DOIUrl":"https://doi.org/10.2139/ssrn.2970482","url":null,"abstract":"In an urban economy, the distribution of people and real estate prices depends on the location of the central business district of a city. As distance from the city center increases, both prices and population density diminish, for travel costs increase in terms of time and money. As manufacturing gradually leaves the cities, the importance of consumer amenities as attractors of population to the urban areas increases. The role of a business center is being replaced by the consumer center. In this paper, we identify the location of the consumer center of St. Petersburg - the second largest city in Russia and its former capital. For this purpose using the data from open sources in the Internet regarding the location of many different types of urban amenities, the indices of their spatial density are computed. Using the weights based on coefficients of spatial variation and survey-based weights, the individual indices are aggregated to two general centrality indices. Their unique maxima correspond to the city center of St. Petersburg, which is located on Nevsky prospekt, between Fontanka river and Liteinyi prospekt.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114716465","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}
I show how the extensive margin of firm entry and exit can greatly amplify idiosyncratic shocks in an economy with a production network. I show that canonical input-output models, which lack the extensive margin of firm entry and exit, have some crucial limitations. In these models, the systemic importance of a firm does not respond to productivity shocks, depends only on the firm’s role as a supplier, and is equal to or well-approximated by the firm’s size. This means that for every canonical input-output model, there exists a non-interconnected model that has the same aggregate response to productivity shocks. I show that when we allow for entry and exit, the systemic importance of a firm responds endogenously to productivity shocks, depends on a firm’s role not just as a supplier but also as a consumer, and a firm’s systemic influence is no longer well-approximated by its size. Furthermore, I show that nondivisibilities in systemically important industries can cause one failure to snowball into a large-scale avalanche of failures. In this sense, shocks can be amplified as they travel through the network, whereas in canonical input-output models they cannot.
{"title":"Cascading Failures in Production Networks","authors":"D. Baqaee","doi":"10.2139/ssrn.2909868","DOIUrl":"https://doi.org/10.2139/ssrn.2909868","url":null,"abstract":"I show how the extensive margin of firm entry and exit can greatly amplify idiosyncratic shocks in an economy with a production network. I show that canonical input-output models, which lack the extensive margin of firm entry and exit, have some crucial limitations. In these models, the systemic importance of a firm does not respond to productivity shocks, depends only on the firm’s role as a supplier, and is equal to or well-approximated by the firm’s size. This means that for every canonical input-output model, there exists a non-interconnected model that has the same aggregate response to productivity shocks. I show that when we allow for entry and exit, the systemic importance of a firm responds endogenously to productivity shocks, depends on a firm’s role not just as a supplier but also as a consumer, and a firm’s systemic influence is no longer well-approximated by its size. Furthermore, I show that nondivisibilities in systemically important industries can cause one failure to snowball into a large-scale avalanche of failures. In this sense, shocks can be amplified as they travel through the network, whereas in canonical input-output models they cannot.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127736328","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 mathematics, singularity signifies a point at which a given mathematical function or its derivatives is not defined. Singularities are mostly mathematical that occur in the mathematical models describing physical systems. In social science compared to physical science, fewer cases of singularity arise, among which the mostly discussed one is technological singularity. Omnipotent mathematics (OM) is an approach to analyze singularity in a mathematical framework. In this approach “zero” is a non-existent entity which decomposes into quasi-existent entities, which in turn interact with each other to generate an existent entity. The focus of this paper is to address a typical hypothetical singularity problem in economics and try to solve it using omnipotent mathematics. Here the economic input-output model has been used to showcase an economic singularity problem that can be resolved in terms of quasi-existent entity.
{"title":"Can Singularity Problem in Economics be solved by Omnipotent Mathematics?","authors":"T. Das, Ishita Datta Ray","doi":"10.2139/ssrn.2634073","DOIUrl":"https://doi.org/10.2139/ssrn.2634073","url":null,"abstract":"In mathematics, singularity signifies a point at which a given mathematical function or its derivatives is not defined. Singularities are mostly mathematical that occur in the mathematical models describing physical systems. In social science compared to physical science, fewer cases of singularity arise, among which the mostly discussed one is technological singularity. Omnipotent mathematics (OM) is an approach to analyze singularity in a mathematical framework. In this approach “zero” is a non-existent entity which decomposes into quasi-existent entities, which in turn interact with each other to generate an existent entity. The focus of this paper is to address a typical hypothetical singularity problem in economics and try to solve it using omnipotent mathematics. Here the economic input-output model has been used to showcase an economic singularity problem that can be resolved in terms of quasi-existent entity.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129089440","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 estimates the impact of the informal penalty, that is, the cost of exclusion from the mainstream economy, for various stakeholders in the Angeleno ecosystem, from local businesses to neighborhood residents. We investigate three research questions: 1. What is the economic cost of excluding street vendors from the formal economy? 2. What consequences do sidewalk microentrepreneurs have on brick and mortar retail stores and restaurants operating on the same city block? 3. Is there likely to be more or less crime in areas where vendors are present?
{"title":"Sidewalk Stimulus: Economic and Geographic Impacts of Los Angeles Street Vendors","authors":"Yvonne Yen Liu, P. Burns, D. Flaming","doi":"10.2139/ssrn.3380029","DOIUrl":"https://doi.org/10.2139/ssrn.3380029","url":null,"abstract":"This report estimates the impact of the informal penalty, that is, the cost of exclusion from the mainstream economy, for various stakeholders in the Angeleno ecosystem, from local businesses to neighborhood residents. We investigate three research questions: \u0000 \u00001. What is the economic cost of excluding street vendors from the formal economy? \u0000 \u00002. What consequences do sidewalk microentrepreneurs have on brick and mortar retail stores and restaurants operating on the same city block? \u0000 \u00003. Is there likely to be more or less crime in areas where vendors are present?","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127041357","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 : 2015-01-01DOI: 10.5089/9781498393454.001
F. Grigoli, Alexander Herman, Andrew J. Swiston, C. Di Bella
Output gap estimates are subject to a wide range of uncertainty owing to data revisions and the difficulty in distinguishing between cycle and trend in real time. This is important given the central role in monetary policy of assessments of economic activity relative to capacity. We show that country desks tend to overestimate economic slack, especially during recessions, and that uncertainty in initial output gap estimates persists several years. Only a small share of output gap revisions is predictable ex ante based on characteristics like output dynamics, data quality, and policy frameworks. We also show that for a group of Latin American inflation targeters the prescriptions from typical monetary policy rules are subject to large changes due to output gap revisions. These revisions explain a sizable proportion of the deviation of inflation from target, suggesting this information is not accounted for in real-time policy decisions.
{"title":"Output Gap Uncertainty and Real-Time Monetary Policy","authors":"F. Grigoli, Alexander Herman, Andrew J. Swiston, C. Di Bella","doi":"10.5089/9781498393454.001","DOIUrl":"https://doi.org/10.5089/9781498393454.001","url":null,"abstract":"Output gap estimates are subject to a wide range of uncertainty owing to data revisions and the difficulty in distinguishing between cycle and trend in real time. This is important given the central role in monetary policy of assessments of economic activity relative to capacity. We show that country desks tend to overestimate economic slack, especially during recessions, and that uncertainty in initial output gap estimates persists several years. Only a small share of output gap revisions is predictable ex ante based on characteristics like output dynamics, data quality, and policy frameworks. We also show that for a group of Latin American inflation targeters the prescriptions from typical monetary policy rules are subject to large changes due to output gap revisions. These revisions explain a sizable proportion of the deviation of inflation from target, suggesting this information is not accounted for in real-time policy decisions.","PeriodicalId":129620,"journal":{"name":"ERN: Input-Output Models (Topic)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115172605","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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