Governments and organizations often implement policies designed to help people in case of an undesirable event. Such policies can make the society better off, but they may also create moral hazard. We use a laboratory experiment to examine two questions. First, can discretionary decisions to provide assistance overcome the problem of moral hazard and lead to higher efficiency? Second, if so, will people prefer this discretionary procedure to the strict liability policy in which no assistance is provided? We find that the assistance is more ecient than the strict liability procedure. However, people still prefer the strict liability regime rather than assistance provision. We conduct additional treatments that show that this eect is not driven by the presence of the human discretion, nor by risk, loss or inequality aversion. This suggests that when moral hazard is a concern people have procedural preferences in favor of the strict liability regime.
{"title":"Pull yourself up by your bootstraps: Identifying procedural preferences against helping others in the presence of moral hazard","authors":"Staněk Rostislav, Krčál Ondřej, Čellárová Katarína","doi":"10.5817/wp_muni_econ_2021-11","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2021-11","url":null,"abstract":"Governments and organizations often implement policies designed to help people in case of an undesirable event. Such policies can make the society better off, but they may also create moral hazard. We use a laboratory experiment to examine two questions. First, can discretionary decisions to provide assistance overcome the problem of moral hazard and lead to higher efficiency? Second, if so, will people prefer this discretionary procedure to the strict liability policy in which no assistance is provided? We find that the assistance is more ecient than the strict liability procedure. However, people still prefer the strict liability regime rather than assistance provision. We conduct additional treatments that show that this eect is not driven by the presence of the human discretion, nor by risk, loss or inequality aversion. This suggests that when moral hazard is a concern people have procedural preferences in favor of the strict liability regime.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115628851","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2022-07
Fazio Andrea, Reggiani Tommaso
We suggest that people advocate for equality also because they fear income losses below a given reference point. Stabilizing their baseline income can make workers more tolerant of inequality. We present evidence of this attitude in the UK by exploiting the introduction of the National Minimum Wage (NMW), which institutionally set a baseline pay reducing the risk of income losses for British workers at the bottom of the income distribution. Based on data from the British Household Panel Survey, we show that workers that benefited from the NMW program became relatively more tolerant of inequality and more likely to vote for the Conservative party.
{"title":"Minimum wage and tolerance for inequality","authors":"Fazio Andrea, Reggiani Tommaso","doi":"10.5817/wp_muni_econ_2022-07","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2022-07","url":null,"abstract":"We suggest that people advocate for equality also because they fear income losses below a given reference point. Stabilizing their baseline income can make workers more tolerant of inequality. We present evidence of this attitude in the UK by exploiting the introduction of the National Minimum Wage (NMW), which institutionally set a baseline pay reducing the risk of income losses for British workers at the bottom of the income distribution. Based on data from the British Household Panel Survey, we show that workers that benefited from the NMW program became relatively more tolerant of inequality and more likely to vote for the Conservative party.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124794949","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2023-07
E. Levi, M. Bayerlein, G. Grimalda, T. Reggiani
Nowadays, immigration is a polarizing topic in politics. In this paper, we investigate how much this political polarization is driven by the depiction narratives made of immigrants vis-a-vis the natives. Furthermore, we look at whether polarization is rooted in private preferences over narratives or in how they are endorsed in public settings and social media. Our empirical strategy consists of a survey experiment in the 2021 German elections and a field experiment on Twitter in which we manipulate the “pinned tweets” of experimental users. To build our narratives, we manipulate either the policy position — hostile toward or accepting migration — or an emphasis on the out-group, on the in-group, or on economic reciprocity. We find that political polarization is driven both by the policy position and emphasis in narratives. On Twitter, the out-group emphasis drives supporters of different parties apart, and the corresponding hostile narrative becomes the only one going viral. In the survey, right-wing participants prefer the reciprocity emphasis more, but we still find evidence of more polarization when allowing the participants to go public.
{"title":"Narratives on migration and political polarization: How the emphasis in narratives can drive us apart","authors":"E. Levi, M. Bayerlein, G. Grimalda, T. Reggiani","doi":"10.5817/wp_muni_econ_2023-07","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2023-07","url":null,"abstract":"Nowadays, immigration is a polarizing topic in politics. In this paper, we investigate how much this political polarization is driven by the depiction narratives made of immigrants vis-a-vis the natives. Furthermore, we look at whether polarization is rooted in private preferences over narratives or in how they are endorsed in public settings and social media. Our empirical strategy consists of a survey experiment in the 2021 German elections and a field experiment on Twitter in which we manipulate the “pinned tweets” of experimental users. To build our narratives, we manipulate either the policy position — hostile toward or accepting migration — or an emphasis on the out-group, on the in-group, or on economic reciprocity. We find that political polarization is driven both by the policy position and emphasis in narratives. On Twitter, the out-group emphasis drives supporters of different parties apart, and the corresponding hostile narrative becomes the only one going viral. In the survey, right-wing participants prefer the reciprocity emphasis more, but we still find evidence of more polarization when allowing the participants to go public.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115017945","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2021-02
Abraham Diya, Greiner Ben, Stephanides Marianne
In order to decrease social distance and increase trust on their platforms, many online marketplaces allow traders to be represented by profile pictures or avatars. In a laboratory experiment, we investigate whether the presence of seller avatars affects trading behavior in a market. We contrast markets without avatars with markets where avatars truthfully represent traders and markets where avatars can be freely changed at any time and may thus be chosen strategically. At the aggregate level, we find that the presence of truthful avatars increases the trustwothiness of sellers, but that this effect is undone when avatars can be chosen strategically. We do not detect aggregate effects on buyers´ trusting choices. Female avatars are more trusted, and correspondignly in the treatment with free avatar choice men are more likely to represent themselves with a female avatar than vice versa.
{"title":"On the Internet you can be anyone: An experiment on strategic avatar choice in online marketplaces","authors":"Abraham Diya, Greiner Ben, Stephanides Marianne","doi":"10.5817/wp_muni_econ_2021-02","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2021-02","url":null,"abstract":"In order to decrease social distance and increase trust on their platforms, many online marketplaces allow traders to be represented by profile pictures or avatars. In a laboratory experiment, we investigate whether the presence of seller avatars affects trading behavior in a market. We contrast markets without avatars with markets where avatars truthfully represent traders and markets where avatars can be freely changed at any time and may thus be chosen strategically. At the aggregate level, we find that the presence of truthful avatars increases the trustwothiness of sellers, but that this effect is undone when avatars can be chosen strategically. We do not detect aggregate effects on buyers´ trusting choices. Female avatars are more trusted, and correspondignly in the treatment with free avatar choice men are more likely to represent themselves with a female avatar than vice versa.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122472564","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}
Social media play a relevant role in shaping social attitudes and economic behaviors of individuals. One of the first very well-known examples of social media campaign is the Ice Bucket Challenge (IBC), a charity campaign that went viral on social networks in August 2014 aiming at collecting money for the research on amyotrophic lateral sclerosis (ALS). We rely on UK longitudinal data to investigate the causal impact of the Ice Bucket Challenge on pro-social behaviors. In detail, this study shows that having been exposed to the IBC increases the probability of donating money, and it increases the amount of donating money among those who donate at most £100. We also find that exposure to the IBC has increased the probability of volunteering and the level of interpersonal trust. However, all these results, but the one on the intensive margins of donations, have a short duration, limited to less than one year, supporting the prevalent consensus that social media campaigns may have only short-term effects.
{"title":"Social media charity campaigns and pro-social behavior. Evidence from the Ice Bucket Challenge","authors":"Fazio Andrea, Scervini Francesco, Reggiani Tommaso","doi":"10.5817/wp_muni_econ_2022-09","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2022-09","url":null,"abstract":"Social media play a relevant role in shaping social attitudes and economic behaviors of individuals. One of the first very well-known examples of social media campaign is the Ice Bucket Challenge (IBC), a charity campaign that went viral on social networks in August 2014 aiming at collecting money for the research on amyotrophic lateral sclerosis (ALS). We rely on UK longitudinal data to investigate the causal impact of the Ice Bucket Challenge on pro-social behaviors. In detail, this study shows that having been exposed to the IBC increases the probability of donating money, and it increases the amount of donating money among those who donate at most £100. We also find that exposure to the IBC has increased the probability of volunteering and the level of interpersonal trust. However, all these results, but the one on the intensive margins of donations, have a short duration, limited to less than one year, supporting the prevalent consensus that social media campaigns may have only short-term effects.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131800196","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2022-10
Corazzini Luca, Matteo M. Marini
This paper is a single-project meta-analysis of four experiments that first model charitable giving as individual contributions to a multiplicity of competing threshold public goods. Given the centrality of the coordination dilemma as the number of recipients increases, we pool 15,936 observations at the individual level for the purpose of identifying the most effective focal points, their mechanics, and their implications for donors’ wealth. We find that competition between public goods implies massive coordination problems that originate from fewer contributions and result in lower profits. In this setting, the most powerful coordination device turns out to be the existence of a single contribution option that stands out on its merits. We also observe an inverted U-shaped trend in the successful provision of public goods, offering evidence for experience as a focal point peculiar to the multiple-public-good framework. The effective focal points do not leverage greater contributions to solve the coordination dilemma, yet they generate higher earnings. Finally, delegation proves to be a sound device for reducing the risk of miscoordination as long as the delegate is formally obliged to pass along a high enough percentage of the transferred resources. We discuss possible implications of our findings.
{"title":"Focal points in multiple threshold public goods games: A single-project meta-analysis","authors":"Corazzini Luca, Matteo M. Marini","doi":"10.5817/wp_muni_econ_2022-10","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2022-10","url":null,"abstract":"This paper is a single-project meta-analysis of four experiments that first model charitable giving as individual contributions to a multiplicity of competing threshold public goods. Given the centrality of the coordination dilemma as the number of recipients increases, we pool 15,936 observations at the individual level for the purpose of identifying the most effective focal points, their mechanics, and their implications for donors’ wealth. We find that competition between public goods implies massive coordination problems that originate from fewer contributions and result in lower profits. In this setting, the most powerful coordination device turns out to be the existence of a single contribution option that stands out on its merits. We also observe an inverted U-shaped trend in the successful provision of public goods, offering evidence for experience as a focal point peculiar to the multiple-public-good framework. The effective focal points do not leverage greater contributions to solve the coordination dilemma, yet they generate higher earnings. Finally, delegation proves to be a sound device for reducing the risk of miscoordination as long as the delegate is formally obliged to pass along a high enough percentage of the transferred resources. We discuss possible implications of our findings.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128788151","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2019-01
Fišar Miloš, Krčál Ondřej, Staněk Rostislav, Špalek Jiří
Periodic rotation of staff in public administration may lead to lower corruption, as it disrupts long-term relationships between public officials and potential bribers. This paper proposes an experimental design that tests the anti-corruption effect of staff rotation in situations where public officials have committed to reciprocating bribes. We find that staff rotation does not influence the proportion of firms offering bribes but does reduce the share of bribe acceptance and inefficient decisions owing to bribery. The outcome of the staff-rotation treatment, in which firms offered bribes even though they were rarely accepted by officials, is consistent with the game having a quantal response equilibrium.
{"title":"The Effects of Staff-rotation in Public Administration on the Decision to Bribe or be Bribed","authors":"Fišar Miloš, Krčál Ondřej, Staněk Rostislav, Špalek Jiří","doi":"10.5817/wp_muni_econ_2019-01","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2019-01","url":null,"abstract":"Periodic rotation of staff in public administration may lead to lower corruption, as it disrupts long-term relationships between public officials and potential bribers. This paper proposes an experimental design that tests the anti-corruption effect of staff rotation in situations where public officials have committed to reciprocating bribes. We find that staff rotation does not influence the proportion of firms offering bribes but does reduce the share of bribe acceptance and inefficient decisions owing to bribery. The outcome of the staff-rotation treatment, in which firms offered bribes even though they were rarely accepted by officials, is consistent with the game having a quantal response equilibrium.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"357 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122713934","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 : 1900-01-01DOI: 10.5817/wp_muni_econ_2022-06
Mikula Štěpán, Reggiani Tommaso
Through a correspondence study, this paper investigates whether employers discriminate job applicants based on their living conditions. Exploiting the natural setting provided by a Rapid Re-housing Program, we sent 1,347 job applications for low-qualified front-desk jobs in Brno, Czech Republic. The resumes exogenously differed in only one main aspect represented by the address of the applicants, signaling both the quality of the neighborhood and the quality of the housing conditions in which they were living. We found that while the higher quality of the district has a strong effect in increasing the hiring chances (+20%) the actual improvement of the living conditions standards, per se, does not generate any significant positive effect.
{"title":"Residential-based discrimination in the labor market","authors":"Mikula Štěpán, Reggiani Tommaso","doi":"10.5817/wp_muni_econ_2022-06","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2022-06","url":null,"abstract":"Through a correspondence study, this paper investigates whether employers discriminate job applicants based on their living conditions. Exploiting the natural setting provided by a Rapid Re-housing Program, we sent 1,347 job applications for low-qualified front-desk jobs in Brno, Czech Republic. The resumes exogenously differed in only one main aspect represented by the address of the applicants, signaling both the quality of the neighborhood and the quality of the housing conditions in which they were living. We found that while the higher quality of the district has a strong effect in increasing the hiring chances (+20%) the actual improvement of the living conditions standards, per se, does not generate any significant positive effect.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115230935","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}
There has been an increasing interest in altruistic behaviour in the domain of losses recently. Nevertheless, there is no consensus in whether the monetary losses make individuals more generous or more selfish. Although almost all relevant studies rely on a dictator game to study altruistic behaviour, the experimental designs of these studies differ in how the losses are framed, which may explain the diverging findings. Utilizing a dictator game, this paper studies the impact of loss framing on altruism. The main methodological result is that the dictators’ prosocial behaviour is sensitive to the loss frame they are embedded in. More specifically, in a dictator game in which the dictators have to share a loss between themselves and a recipient, the monetary allocations of the dictators are more benevolent than in a standard setting without a loss and in a dictator game in which the dictators have to share what remains of their endowments after a loss. These differences are explained by the different social norms that the respective loss frames invoke.
{"title":"Mind the framing when studying social preferences in the domain of losses","authors":"Antinyan Armenak, Corazzini Luca, Fišar Miloš, Reggiani Tommaso","doi":"10.5817/wp_muni_econ_2022-11","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2022-11","url":null,"abstract":"There has been an increasing interest in altruistic behaviour in the domain of losses recently. Nevertheless, there is no consensus in whether the monetary losses make individuals more generous or more selfish. Although almost all relevant studies rely on a dictator game to study altruistic behaviour, the experimental designs of these studies differ in how the losses are framed, which may explain the diverging findings. Utilizing a dictator game, this paper studies the impact of loss framing on altruism. The main methodological result is that the dictators’ prosocial behaviour is sensitive to the loss frame they are embedded in. More specifically, in a dictator game in which the dictators have to share a loss between themselves and a recipient, the monetary allocations of the dictators are more benevolent than in a standard setting without a loss and in a dictator game in which the dictators have to share what remains of their endowments after a loss. These differences are explained by the different social norms that the respective loss frames invoke.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"09 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125154901","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}
Experimental studies have modeled individual funding of social projects as contributions to a threshold public good. We examine donors’ behavior when they face multiple threshold public goods and the possibility of coordinating their contributions via an intermediary. Employing the experimental design developed in Corazzini, Cotton, and Reggiani (2020), we vary both the size of a ‘destination rule’, which places restrictions on the intermediary’s use of a donor’s funds, as well as the overhead cost of the intermediary, modeled as a sunk cost incurred by the intermediary whether or not any of the public goods are successfully funded. We show that subjects behave in line with equilibrium predictions with regard to the size of the destination rule, only increasing their contributions in the presence of a relatively high destination rule that prevents expropriation by the intermediary. However, we find that the positive effect of a high destination rule is undone in the presence of overhead sunk costs on the intermediary, thus providing evidence in favor of the sunk-cost bias and ‘overhead aversion’ that are commonly exhibited by donors exhibit when selecting charities.
{"title":"Delegation and Overhead Aversion with Multiple Threshold Public Goods","authors":"Diya Abraham, Corazzini Luca, Fišar Miloš, Reggiani Tommaso","doi":"10.5817/wp_muni_econ_2021-14","DOIUrl":"https://doi.org/10.5817/wp_muni_econ_2021-14","url":null,"abstract":"Experimental studies have modeled individual funding of social projects as contributions to a threshold public good. We examine donors’ behavior when they face multiple threshold public goods and the possibility of coordinating their contributions via an intermediary. Employing the experimental design developed in Corazzini, Cotton, and Reggiani (2020), we vary both the size of a ‘destination rule’, which places restrictions on the intermediary’s use of a donor’s funds, as well as the overhead cost of the intermediary, modeled as a sunk cost incurred by the intermediary whether or not any of the public goods are successfully funded. We show that subjects behave in line with equilibrium predictions with regard to the size of the destination rule, only increasing their contributions in the presence of a relatively high destination rule that prevents expropriation by the intermediary. However, we find that the positive effect of a high destination rule is undone in the presence of overhead sunk costs on the intermediary, thus providing evidence in favor of the sunk-cost bias and ‘overhead aversion’ that are commonly exhibited by donors exhibit when selecting charities.","PeriodicalId":188529,"journal":{"name":"MUNI ECON Working Papers","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130150590","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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