We construct a dynamic model of election campaigns. In the model, opportunities for candidates to refine/clarify their policy positions are limited and arrive stochastically along the course of the campaign until the predetermined election date. We show that this simple friction leads to rich and subtle campaign dynamics. We first demonstrate these effects in a series of canonical static models of elections that we extend to dynamic settings, including models with valence and a multi-dimensional policy space. We then present general principles that underlie the results from those models. In particular, we establish that candidates spend a long time using ambiguous language during the election campaign in equilibrium. ∗Kamada: Haas School of Business, University of California, Berkeley, Berkeley, CA 94720, e-mail: y.cam.24@gmail.com. Sugaya: Stanford Graduate School of Business, Stanford, CA, 94305, e-mail: tsugaya@stanford.edu; We thank Ernesto Dal Bo, Itay Fainmesser, Drew Fudenberg, Michihiro Kandori, Akitada Kasahara, Kei Kawai, Fuhito Kojima, David Laibson, John B. Londregan, Shih-En Lu, Francisco Mart́ınez-Mora, Adam H. Meirowitz, Stephen Morris, Kristopher Ramsay, Andrzej Skrzypacz, Ken Shepsle, Yuki Takagi, Satoru Takahashi, and the seminar participants at the Harvard University Department of Economics and Department of Government, the Princeton University Department of Economics and Department of Political Science, University of California, Berkeley, Yale University, the 21st Stony Brook International Conference on Game Theory, and the Urrutia Elejalde Workshop on Information, Dynamics and Political Decision Making for helpful comments. In addition, Steven Callander and Josh Gottlieb read through the previous versions of this paper and gave us very detailed comments, which significantly improved the paper. We also thank the careful reading and suggestions by the Editor and the referees. Judith Levi provided a superb professional editorial assistance, which again significantly improved the paper. We thank Emily Her, Douglas Hong, Omair Butt, and especially Lingxuan Wu for their excellent research assistantship. This paper subsumes and supersedes part of our unpublished working paper “Valence Candidates and Ambiguous Platforms in Policy Announcement Games” and its earlier version circulated as “Policy Announcement Game: Valence Candidates and Ambiguous Policies,” which Sugaya first presented at the 21st Stony Brook International Conference on Game Theory in 2010.
{"title":"Optimal Timing of Policy Announcements in Dynamic Election Campaigns*","authors":"Yuichiro Kamada, Takuo Sugaya","doi":"10.1093/qje/qjaa010","DOIUrl":"https://doi.org/10.1093/qje/qjaa010","url":null,"abstract":"We construct a dynamic model of election campaigns. In the model, opportunities for candidates to refine/clarify their policy positions are limited and arrive stochastically along the course of the campaign until the predetermined election date. We show that this simple friction leads to rich and subtle campaign dynamics. We first demonstrate these effects in a series of canonical static models of elections that we extend to dynamic settings, including models with valence and a multi-dimensional policy space. We then present general principles that underlie the results from those models. In particular, we establish that candidates spend a long time using ambiguous language during the election campaign in equilibrium. ∗Kamada: Haas School of Business, University of California, Berkeley, Berkeley, CA 94720, e-mail: y.cam.24@gmail.com. Sugaya: Stanford Graduate School of Business, Stanford, CA, 94305, e-mail: tsugaya@stanford.edu; We thank Ernesto Dal Bo, Itay Fainmesser, Drew Fudenberg, Michihiro Kandori, Akitada Kasahara, Kei Kawai, Fuhito Kojima, David Laibson, John B. Londregan, Shih-En Lu, Francisco Mart́ınez-Mora, Adam H. Meirowitz, Stephen Morris, Kristopher Ramsay, Andrzej Skrzypacz, Ken Shepsle, Yuki Takagi, Satoru Takahashi, and the seminar participants at the Harvard University Department of Economics and Department of Government, the Princeton University Department of Economics and Department of Political Science, University of California, Berkeley, Yale University, the 21st Stony Brook International Conference on Game Theory, and the Urrutia Elejalde Workshop on Information, Dynamics and Political Decision Making for helpful comments. In addition, Steven Callander and Josh Gottlieb read through the previous versions of this paper and gave us very detailed comments, which significantly improved the paper. We also thank the careful reading and suggestions by the Editor and the referees. Judith Levi provided a superb professional editorial assistance, which again significantly improved the paper. We thank Emily Her, Douglas Hong, Omair Butt, and especially Lingxuan Wu for their excellent research assistantship. This paper subsumes and supersedes part of our unpublished working paper “Valence Candidates and Ambiguous Platforms in Policy Announcement Games” and its earlier version circulated as “Policy Announcement Game: Valence Candidates and Ambiguous Policies,” which Sugaya first presented at the 21st Stony Brook International Conference on Game Theory in 2010.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"1725-1797"},"PeriodicalIF":13.7,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjaa010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42359704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I study how a credit crunch affects output price dynamics. I build a unique micro-level data set that combines scanner-level prices and quantities with producer information, including the producer’s banking relationships, inventory, and cash holdings. I exploit the Lehman Brothers failure as a quasi-experiment and find that the firms facing a negative credit supply shock decrease their output prices approximately 15% more than their unaffected counterparts. I hypothesize that such firms reduce prices to liquidate inventory and generate additional cash flow from the product market. I find strong empirical support for this hypothesis: (i) the firms that face a negative bank shock temporarily decrease their prices and inventory and increase their market share and cash holdings relative to their counterparts, and (ii) this effect is stronger for the firms and sectors with a high initial inventory or small initial cash holdings.
{"title":"The Effect of the Credit Crunch on Output Price Dynamics: The Corporate Inventory and Liquidity Management Channel*","authors":"Ryan Kim","doi":"10.1093/qje/qjaa025","DOIUrl":"https://doi.org/10.1093/qje/qjaa025","url":null,"abstract":"\u0000 I study how a credit crunch affects output price dynamics. I build a unique micro-level data set that combines scanner-level prices and quantities with producer information, including the producer’s banking relationships, inventory, and cash holdings. I exploit the Lehman Brothers failure as a quasi-experiment and find that the firms facing a negative credit supply shock decrease their output prices approximately 15% more than their unaffected counterparts. I hypothesize that such firms reduce prices to liquidate inventory and generate additional cash flow from the product market. I find strong empirical support for this hypothesis: (i) the firms that face a negative bank shock temporarily decrease their prices and inventory and increase their market share and cash holdings relative to their counterparts, and (ii) this effect is stronger for the firms and sectors with a high initial inventory or small initial cash holdings.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":" ","pages":""},"PeriodicalIF":13.7,"publicationDate":"2020-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjaa025","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47325710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study optimal spatial policies in a quantitative trade and geography framework with spillovers and spatial sorting of heterogeneous workers. We characterize the spatial transfers that must hold in efficient allocations, as well as labor subsidies that can implement them. There exists scope for welfare-enhancing spatial policies even when spillovers are common across locations. Using data on U.S. cities and existing estimates of the spillover elasticities, we find that the U.S. economy would benefit from a reallocation of workers to currently low-wage cities. The optimal allocation features a greater share of high-skill workers in smaller cities relative to the observed allocation. Inefficient sorting may lead to substantial welfare costs.
{"title":"Optimal Spatial Policies, Geography, and Sorting*","authors":"Pablo D. Fajgelbaum, C. Gaubert","doi":"10.1093/qje/qjaa001","DOIUrl":"https://doi.org/10.1093/qje/qjaa001","url":null,"abstract":"\u0000 We study optimal spatial policies in a quantitative trade and geography framework with spillovers and spatial sorting of heterogeneous workers. We characterize the spatial transfers that must hold in efficient allocations, as well as labor subsidies that can implement them. There exists scope for welfare-enhancing spatial policies even when spillovers are common across locations. Using data on U.S. cities and existing estimates of the spillover elasticities, we find that the U.S. economy would benefit from a reallocation of workers to currently low-wage cities. The optimal allocation features a greater share of high-skill workers in smaller cities relative to the observed allocation. Inefficient sorting may lead to substantial welfare costs.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"959-1036"},"PeriodicalIF":13.7,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjaa001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42390325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We develop a theory of how an agent makes basic multiproduct consumption decisions in the presence of taste, consumption opportunity, and price shocks that are costly to attend to. We establish that the agent often simplifies her choices by restricting attention to a few important considerations, which depend on the decision at hand and affect her consumption patterns in specific ways. If the agent’s problem is to choose the consumption levels of many goods with different degrees of substitutability, then she may create mental budgets for more substitutable products (e.g., entertainment). In some situations, it is optimal to specify budgets in terms of consumption quantities, but when most products have an abundance of substitutes, specifying budgets in terms of nominal spending tends to be optimal. If the goods are complements, in contrast, then the agent may—consistent with naive diversification—choose a fixed, unconsidered mix of products. And if the agent’s problem is to choose one of multiple products to fulfill a given consumption need (e.g., for gasoline or a bed), then it is often optimal for her to allocate a fixed sum for the need. JEL Codes: D01, D11, D14
{"title":"Choice Simplification: A Theory of Mental Budgeting and Naive Diversification*","authors":"B. Kőszegi, Filip Matějka","doi":"10.1093/qje/qjz043","DOIUrl":"https://doi.org/10.1093/qje/qjz043","url":null,"abstract":"We develop a theory of how an agent makes basic multiproduct consumption decisions in the presence of taste, consumption opportunity, and price shocks that are costly to attend to. We establish that the agent often simplifies her choices by restricting attention to a few important considerations, which depend on the decision at hand and affect her consumption patterns in specific ways. If the agent’s problem is to choose the consumption levels of many goods with different degrees of substitutability, then she may create mental budgets for more substitutable products (e.g., entertainment). In some situations, it is optimal to specify budgets in terms of consumption quantities, but when most products have an abundance of substitutes, specifying budgets in terms of nominal spending tends to be optimal. If the goods are complements, in contrast, then the agent may—consistent with naive diversification—choose a fixed, unconsidered mix of products. And if the agent’s problem is to choose one of multiple products to fulfill a given consumption need (e.g., for gasoline or a bed), then it is often optimal for her to allocate a fixed sum for the need. JEL Codes: D01, D11, D14","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"1153-1207"},"PeriodicalIF":13.7,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjz043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49621679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Building on a textbook description of associative memory (Kahana 2012), we present a model of choice in which a choice option cues recall of similar past experiences. Memory shapes valuation and decisions in two ways. First, recalled experiences form a norm, which serves as an initial anchor for valuation. Second, salient quality and price surprises relative to the norm lead to large adjustments in valuation. The model unifies many well-documented choice puzzles, including the attribution and projection biases, inattention to hidden attributes, background contrast effects, and context-dependent willingness to pay. Unifying these puzzles on the basis of selective memory and attention to surprise yields multiple new predictions.
{"title":"Memory, Attention, and Choice*","authors":"P. Bordalo, N. Gennaioli, A. Shleifer","doi":"10.1093/qje/qjaa007","DOIUrl":"https://doi.org/10.1093/qje/qjaa007","url":null,"abstract":"\u0000 Building on a textbook description of associative memory (Kahana 2012), we present a model of choice in which a choice option cues recall of similar past experiences. Memory shapes valuation and decisions in two ways. First, recalled experiences form a norm, which serves as an initial anchor for valuation. Second, salient quality and price surprises relative to the norm lead to large adjustments in valuation. The model unifies many well-documented choice puzzles, including the attribution and projection biases, inattention to hidden attributes, background contrast effects, and context-dependent willingness to pay. Unifying these puzzles on the basis of selective memory and attention to surprise yields multiple new predictions.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":" ","pages":""},"PeriodicalIF":13.7,"publicationDate":"2020-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjaa007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42266749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study patterns of behavior in bilateral bargaining situations using a rich, new dataset describing over 88 million listings from eBay's Best Offer platform, with back-and-forth bargaining occurring in over 25 million of these listings. We document patterns of behavior and relate them to "rational" and "psychological" theories of bargaining and find that bargaining patterns are consistent with elements of both approaches. Most notably, players with more bargaining strength typically receive better outcomes, and players exhibit equitable behavior by making offers that split-the-difference between negotiating positions. We are publicly releasing this new dataset to support additional empirical bargaining research.
我们使用一个丰富的新数据集来研究双边讨价还价情况下的行为模式，该数据集描述了eBay Best Offer平台上超过8800万件物品，其中超过2500万件物品中发生了来回讨价还价。我们记录了行为模式，并将其与议价的“理性”和“心理”理论联系起来，发现议价模式与两种方法的要素是一致的。最值得注意的是，具有更强议价能力的玩家通常会获得更好的结果，并且玩家通过在谈判立场之间提供折中方案而表现出公平的行为。我们公开发布这个新数据集，以支持额外的实证议价研究。
{"title":"Sequential Bargaining in the Field: Evidence from Millions of Online Bargaining Interactions*","authors":"M. Backus, Thomas Blake, B. Larsen, S. Tadelis","doi":"10.1093/QJE/QJAA003","DOIUrl":"https://doi.org/10.1093/QJE/QJAA003","url":null,"abstract":"We study patterns of behavior in bilateral bargaining situations using a rich, new dataset describing over 88 million listings from eBay's Best Offer platform, with back-and-forth bargaining occurring in over 25 million of these listings. We document patterns of behavior and relate them to \"rational\" and \"psychological\" theories of bargaining and find that bargaining patterns are consistent with elements of both approaches. Most notably, players with more bargaining strength typically receive better outcomes, and players exhibit equitable behavior by making offers that split-the-difference between negotiating positions. We are publicly releasing this new dataset to support additional empirical bargaining research.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"1319-1361"},"PeriodicalIF":13.7,"publicationDate":"2020-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/QJE/QJAA003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43903947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pablo D. Fajgelbaum, P. Goldberg, P. Kennedy, A. Khandelwal
After decades of supporting free trade, in 2018 the United States raised import tariffs and major trade partners retaliated. We analyze the short-run impact of this return to protectionism on the U.S. economy. Import and retaliatory tariffs caused large declines in imports and exports. Prices of imports targeted by tariffs did not fall, implying complete pass-through of tariffs to duty-inclusive prices. The resulting losses to U.S. consumers and firms that buy imports was $51 billion, or 0.27% of GDP. We embed the estimated trade elasticities in a general-equilibrium model of the U.S. economy. After accounting for tariff revenue and gains to domestic producers, the aggregate real income loss was $7.2 billion, or 0.04% of GDP. Import tariffs favored sectors concentrated in politically competitive counties, and the model implies that tradeable-sector workers in heavily Republican counties were the most negatively affected due to the retaliatory tariffs. JEL Code: F1.
{"title":"The Return to Protectionism*","authors":"Pablo D. Fajgelbaum, P. Goldberg, P. Kennedy, A. Khandelwal","doi":"10.1093/QJE/QJZ036","DOIUrl":"https://doi.org/10.1093/QJE/QJZ036","url":null,"abstract":"After decades of supporting free trade, in 2018 the United States raised import tariffs and major trade partners retaliated. We analyze the short-run impact of this return to protectionism on the U.S. economy. Import and retaliatory tariffs caused large declines in imports and exports. Prices of imports targeted by tariffs did not fall, implying complete pass-through of tariffs to duty-inclusive prices. The resulting losses to U.S. consumers and firms that buy imports was $51 billion, or 0.27% of GDP. We embed the estimated trade elasticities in a general-equilibrium model of the U.S. economy. After accounting for tariff revenue and gains to domestic producers, the aggregate real income loss was $7.2 billion, or 0.04% of GDP. Import tariffs favored sectors concentrated in politically competitive counties, and the model implies that tradeable-sector workers in heavily Republican counties were the most negatively affected due to the retaliatory tariffs. JEL Code: F1.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"1-55"},"PeriodicalIF":13.7,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/QJE/QJZ036","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44203365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paul J. Eliason, Benjamin Heebsh, R. McDevitt, James W. Roberts
Many industries have become increasingly concentrated through mergers and acquisitions, which in health care may have important consequences for spending and outcomes. Using a rich panel of Medicare claims data for nearly one million dialysis patients, we advance the literature on the effects of mergers and acquisitions by studying the precise ways providers change their behavior following an acquisition. We base our empirical analysis on more than 1,200 acquisitions of independent dialysis facilities by large chains over a 12-year period and find that chains transfer several prominent strategies to the facilities they acquire. Most notably, acquired facilities converge to the behavior of their new parent companies by increasing patients’ doses of highly reimbursed drugs, replacing high-skill nurses with less-skilled technicians, and waitlisting fewer patients for kidney transplants. We then show that patients fare worse as a result of these changes: outcomes such as hospitalizations and mortality deteriorate, with our long panel allowing us to identify these effects from within-facility or within-patient variation around the acquisitions. Because overall Medicare spending increases at acquired facilities, mostly as a result of higher drug reimbursements, this decline in quality corresponds to a decline in value for payers. We conclude the article by considering the channels through which acquisitions produce such large changes in provider behavior and outcomes, finding that increased market power cannot explain the decline in quality. Rather, the adoption of the acquiring firm’s strategies and practices drives our main results, with greater economies of scale for drug purchasing responsible for more than half of the change in profits following an acquisition.
{"title":"How Acquisitions Affect Firm Behavior and Performance: Evidence from the Dialysis Industry*","authors":"Paul J. Eliason, Benjamin Heebsh, R. McDevitt, James W. Roberts","doi":"10.1093/qje/qjz034","DOIUrl":"https://doi.org/10.1093/qje/qjz034","url":null,"abstract":"Many industries have become increasingly concentrated through mergers and acquisitions, which in health care may have important consequences for spending and outcomes. Using a rich panel of Medicare claims data for nearly one million dialysis patients, we advance the literature on the effects of mergers and acquisitions by studying the precise ways providers change their behavior following an acquisition. We base our empirical analysis on more than 1,200 acquisitions of independent dialysis facilities by large chains over a 12-year period and find that chains transfer several prominent strategies to the facilities they acquire. Most notably, acquired facilities converge to the behavior of their new parent companies by increasing patients’ doses of highly reimbursed drugs, replacing high-skill nurses with less-skilled technicians, and waitlisting fewer patients for kidney transplants. We then show that patients fare worse as a result of these changes: outcomes such as hospitalizations and mortality deteriorate, with our long panel allowing us to identify these effects from within-facility or within-patient variation around the acquisitions. Because overall Medicare spending increases at acquired facilities, mostly as a result of higher drug reimbursements, this decline in quality corresponds to a decline in value for payers. We conclude the article by considering the channels through which acquisitions produce such large changes in provider behavior and outcomes, finding that increased market power cannot explain the decline in quality. Rather, the adoption of the acquiring firm’s strategies and practices drives our main results, with greater economies of scale for drug purchasing responsible for more than half of the change in profits following an acquisition.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"135 1","pages":"221-267"},"PeriodicalIF":13.7,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/qje/qjz034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46567614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-29DOI: 10.1186/s13567-019-0722-3
Ana Cláudia A Albuquerque, Cesar Cristiano Bassetto, Fabiana A Almeida, Katie A Hildersley, Tom N McNeilly, Collette Britton, Alessandro F T Amarante
Understanding the immunological basis of resistance to gastrointestinal nematode infections in livestock is important in order to develop novel methods of parasite control such as vaccination or genetic selection for parasite resistance. The present study aimed to investigate differences in immune response between parasite resistant Santa Ines and susceptible Ile de France sheep breeds to natural Haemonchus contortus infection. Parasitological parameters, humoral immunity, local and circulating cellular immune responses were evaluated in 19 Santa Ines and 19 Ile de France lambs undergoing different anthelmintic treatments regimens: suppressive treatments (SUP) or targeted selective treatments (TST) over a 5-month grazing period. Santa Ines lambs had significantly lower Haemonchus faecal egg count and worm burden compared to Ile de France regardless of treatment regime. In addition, circulating blood eosinophils count and parasite-specific IgG levels were significantly higher and more rapidly induced in Santa Ines lambs. Abomasal immune responses were generally greater in the resistant breed, which had significantly higher levels of parasite-specific IgA in mucus, and elevated number of globule leukocytes and CD3+ T cells within the abomasal mucosal. Furthermore, numbers of POU2F3+ epithelial cells, a tuft-cell specific transcription factor, were also elevated in the Santa Ines breed, suggesting that this breed is better able to initiate T-helper type 2 immune responses within the abomasum. In conclusion, the differential immunological responses detailed here are relevant to understanding resistance to gastrointestinal nematodes in other host breeds, as well as to resistance breeding as a sustainable control approach for parasitic infections.
了解牲畜对胃肠道线虫感染产生抵抗力的免疫学基础对于开发新型寄生虫控制方法（如疫苗接种或寄生虫抵抗力基因选择）非常重要。本研究旨在调查对寄生虫有抵抗力的圣伊内斯羊和对寄生虫有敏感性的法兰西岛羊对自然感染的柯氏血吸虫的免疫反应差异。在为期 5 个月的放牧期间，对 19 只接受不同抗蠕虫药治疗方案（抑制性治疗（SUP）或靶向选择性治疗（TST））的圣伊内斯绵羊和 19 只法兰西岛绵羊的寄生虫学参数、体液免疫、局部和循环细胞免疫反应进行了评估。与法兰西岛羔羊相比，无论采用哪种治疗方案，圣伊尼斯羔羊的血吸虫粪卵计数和虫体负荷都明显较低。此外，循环血液中的嗜酸性粒细胞数量和寄生虫特异性 IgG 水平在圣伊内斯羔羊中明显更高，而且诱导速度更快。耐药品种羔羊的腹腔免疫反应普遍较强，粘液中寄生虫特异性 IgA 水平明显较高，腹腔粘膜内的球形白细胞和 CD3+ T 细胞数量也有所增加。此外，Santa Ines 品种的 POU2F3+ 上皮细胞（一种簇细胞特异性转录因子）数量也有所增加，这表明该品种能更好地在腹腔内启动 T 辅助型 2 免疫反应。总之，本文详述的不同免疫反应与了解其他宿主品种对胃肠道线虫的抗性以及将抗性育种作为一种可持续的寄生虫感染控制方法有关。
{"title":"Differences in immune responses to Haemonchus contortus infection in the susceptible Ile de France and the resistant Santa Ines sheep under different anthelmintic treatments regimens.","authors":"Ana Cláudia A Albuquerque, Cesar Cristiano Bassetto, Fabiana A Almeida, Katie A Hildersley, Tom N McNeilly, Collette Britton, Alessandro F T Amarante","doi":"10.1186/s13567-019-0722-3","DOIUrl":"10.1186/s13567-019-0722-3","url":null,"abstract":"<p><p>Understanding the immunological basis of resistance to gastrointestinal nematode infections in livestock is important in order to develop novel methods of parasite control such as vaccination or genetic selection for parasite resistance. The present study aimed to investigate differences in immune response between parasite resistant Santa Ines and susceptible Ile de France sheep breeds to natural Haemonchus contortus infection. Parasitological parameters, humoral immunity, local and circulating cellular immune responses were evaluated in 19 Santa Ines and 19 Ile de France lambs undergoing different anthelmintic treatments regimens: suppressive treatments (SUP) or targeted selective treatments (TST) over a 5-month grazing period. Santa Ines lambs had significantly lower Haemonchus faecal egg count and worm burden compared to Ile de France regardless of treatment regime. In addition, circulating blood eosinophils count and parasite-specific IgG levels were significantly higher and more rapidly induced in Santa Ines lambs. Abomasal immune responses were generally greater in the resistant breed, which had significantly higher levels of parasite-specific IgA in mucus, and elevated number of globule leukocytes and CD3+ T cells within the abomasal mucosal. Furthermore, numbers of POU2F3+ epithelial cells, a tuft-cell specific transcription factor, were also elevated in the Santa Ines breed, suggesting that this breed is better able to initiate T-helper type 2 immune responses within the abomasum. In conclusion, the differential immunological responses detailed here are relevant to understanding resistance to gastrointestinal nematodes in other host breeds, as well as to resistance breeding as a sustainable control approach for parasitic infections.</p>","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"105 1","pages":"104"},"PeriodicalIF":3.7,"publicationDate":"2019-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6884896/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90648440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study the persuasive effects of political advertising. Our empirical strategy exploits FCC regulations that result in plausibly exogenous variation in the number of impressions across the borders of neighboring counties. Applying this approach to detailed data on television advertisement broadcasts and viewership patterns during the 2004–12 presidential campaigns, our results indicate that total political advertising has almost no impact on aggregate turnout. By contrast, we find a positive and economically meaningful effect of advertising on candidates’ vote shares. Taken at face value, our estimates imply that a one standard deviation increase in the partisan difference in advertising raises the partisan difference in vote shares by about 0.5 percentage points. Evidence from a regression discontinuity design suggests that advertising affects election results by altering the partisan composition of the electorate.
{"title":"Political Advertising and Election Results","authors":"Jörg L. Spenkuch, D. Toniatti","doi":"10.1093/QJE/QJY010","DOIUrl":"https://doi.org/10.1093/QJE/QJY010","url":null,"abstract":"We study the persuasive effects of political advertising. Our empirical strategy exploits FCC regulations that result in plausibly exogenous variation in the number of impressions across the borders of neighboring counties. Applying this approach to detailed data on television advertisement broadcasts and viewership patterns during the 2004–12 presidential campaigns, our results indicate that total political advertising has almost no impact on aggregate turnout. By contrast, we find a positive and economically meaningful effect of advertising on candidates’ vote shares. Taken at face value, our estimates imply that a one standard deviation increase in the partisan difference in advertising raises the partisan difference in vote shares by about 0.5 percentage points. Evidence from a regression discontinuity design suggests that advertising affects election results by altering the partisan composition of the electorate.","PeriodicalId":48470,"journal":{"name":"Quarterly Journal of Economics","volume":"133 1","pages":"1981-2036"},"PeriodicalIF":13.7,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/QJE/QJY010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43271819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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