Download or read book Essays in the Economics and Econometrics of Networks and Peer Effect written by Zheng Wang and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis contributes to the understanding of peer effects, both methodologically and empirically. The endogeneity of network formation has been a major obstacle to the study of peer influence. The first and the second chapters of the thesis propose a causal identification solution in the potential outcome framework. Combining results from multiple causal inference and statistical network analysis, I show that confounding can be addressed by inferring propensity scores of network link formation from the adjacency matrix. This identification strategy imposes minimum restrictions on the data-generating process and, unlike existing econometric solutions, does not rely on any parametric modelling. As an application, I estimate the effect of high school friendships on bachelor's degree attainment. While previous literature finds that exposure to more high-achieving boys makes girls less likely to obtain a bachelor's degree, I show that if the girls consider the boys as friends, their interactions induce a positive impact instead. Since friendship endogeneity has been addressed, the estimated effect is causal. The third chapter looks at the peer effects generated by group competition. It focuses on the gender differences in preference for competition in a setting where the competition does not involve face-to-face confrontation, and effort is the only determinant of the final ranking. I first develop a model of group competition with heterogeneous preference for ranking. With empirical implications generated from the theoretical model, I then test the gender difference in the preference parameter using web-scraped data from Duolingo, a free online foreign-language learning platform with over 300 million users. Every week, language learners on Duolingo are randomly allocated to groups of 30 people to compete on the number of language lessons completed during that week. The empirical results suggest in this setting, females have a stronger preference for ranking than males.

Download or read book Essays on the Economics of Social Networks written by Won Hee Park and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation consists of two projects, both concerned with how social networks form and how they affect economic decisions. In the first project, entitled Identifying Influential Agents in a Social Network, I define influence centrality, a new measure of influence which combines information on node and neighbor characteristics as well as information on the network structure, by building a model of friendship formation and peer effects and calculating the change in the equilibrium behavior of the network when one node changes its behavior. I apply the model to the context of smoking among middle and high school students and show that a targeted anti-smoking intervention in which a small number of influential smoking students are treated may be more efficient than a uniform program where every student in the school receives the same anti-smoking treatment. The second project, entitled Quantifying Spillovers in Network Formation Over Time, is a joint work with Sean Chu and Shankar Kalyanaraman at Facebook. The goal of the project is to separately identify and understand the relative importance of network effects and unobserved heterogeneity in a multi-period network formation model. Here, we define network effects to be the effect of the number of mutual friends on the probability of friendship and assume that unobserved heterogeneity is time-consistent. We estimate the model on a de-identified panel data set from a small group of users on Facebook and find that both network effects and unobserved heterogeneity are statistically and economically significant predictors of friendship formation on Facebook. We further re-estimate the model first, without network effects and next, without unobserved heterogeneity. Comparing the results from these specifications, we find that network effects play a more important role than unobserved heterogeneity in network formation models on Facebook.

Download or read book Essays on Social and Economic Networks written by Timo Hiller and published by . This book was released on 2011 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis consists of three papers in the field of social and economic networks. In the first, called Peer Effects in Endogenous Networks, I build a model of endogenous net- work formation in the presence of peer effects, which play an important role for decisions concerning educational attainment, criminal activity, labor market participation and R&D expenditures of firms. The class of payoff functions assumed induce local complementar- ities in effort levels and positive local externalities. Links are one-sided and agents move simultaneously in links and effort levels. I find that equilibrium networks display - other than the complete and the empty network - a core-periphery structure, which is commonly observed in empirical studies. Ex-ante homogenous agents may obtain very different ex-post outcomes, depending on the network that arises in equilibrium. Multiplicity of equilibria serves as an explanation for large differences in behaviour across otherwise identical groups. The second paper, titled Alliance Formation and Coercion in Networks, presents a game-theoretic model of network formation, which allows agents to enter bilateral alliances and to extract payoffs from enemies. Each pair of agents creates a surplus of one, which allies divide in equal parts. If agents are enemies, then the agent with more allies obtains a larger share of the surplus. I show that Nash equilibria are of two types. First, a state of utopia, where all agents are allies. Second, asymmetric equilibria, such that agents can be partitioned into sets of different size, where agents within the same set are allies and agents in different sets are enemies. These results stand in contrast to coalition formation games in the economics of conflict literature, where stable group structures are generally symmetric. The model also provides a game-theoretic foundation for structural balance, a long-standing notion in social psychology, which has been fruitfully applied to the study of alliance formation in international relations. The third paper, A Note on Stochastically Stable States for Alliance Formation and Coercion in Networks, introduces dynamics into the model of the second paper and provides a conjecture for stochastically stable states. At every time period t and with fixed probability p, each agent adjusts his strategy myopically, while with small probability E chooses his strategy at random. The configuration where all agents sustain only positive links is shown to not be stochastically stable. Stochastically stable state are thought to be such that the number of cliques is maximal, under a restriction on the relative size of groups.

Download or read book Three Essays on Social Interactions and Networks written by Shenzhe Wang and published by . This book was released on 2014 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation focuses on the social interaction with economic perspectives. This first essay tests peer effects in the workplace with piece-rate compensation. Reference groups are defined as the geographical peers in undirected networks. A series of spatial econometric models are employed to investigate the social effects. We identify and present evidence for endogenous effects (production) while find no evidence for exogenous effects (characteristics). We also find that the heterogeneity of endogenous effects depends on workers and their peers' characteristics, which is defined as conditional endogenous effects in this paper. Our results suggest that rearranging workers' seats according to their personal characteristics could lead to changes in overall productivity. From a field experiment design, the second essay studies the relation between social distance and training outcomes. We test our hypothesis through two measures: the tips shared with trainees by trainers, and the exist test results of trainees. We find that trainers share more tips to socially closer trainees, and the communications between trainers and trainees have a significant indirect effects on the number of tips shared. The productivity of trainees are also higher when they are socially closer to their trainers. The third essay discusses the identification problem in social peers effect studies. By considering the canonical linear in means model with the rank condition in simultaneous equations model, it suggests that the group structures determines the identifiablity of the desired social effects estimates. Transitive networks are not identified unless there are more information contained in the between group structures. Modifications to the conventional model are also suggested with respect to the recovery of transitive networks and potentially incomplete networks.

Download or read book Essays on Network Effects and Money written by Mikael Stenkula and published by . This book was released on 2003 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Essays in the Economics of Networks written by Arun Naresh Advani and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Essays on the Economics of Networks and Social Relations written by Pekka Sääskilahti and published by . This book was released on 2005 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Three Essays on Networks and Public Economics written by Pier-André Bouchard St Amant and published by . This book was released on 2013 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is a collection of three essays. The first two study how ideas spread through a network of individuals, and how it an advertiser can exploit it. In the model I develop, users choose their sources of information based on the perceived usefulness of their sources of information. This contrasts with previous literature where there is no choice made by network users and thus, the information flow is fixed. I provide a complete theoretical characterization of the solution and define a natural measure of influence based on choices of users. I also present an algorithm to solve the model in polynomial time on any network, regardless of the scale or the topology. I also discuss the properties of a network technology from a public economic standpoint. In essence, a network allows the reproduction of ideas for free for the advertiser. If there is any free-riding problem, I show that coalitions of users on the network can solve such problem. I also discuss the social value of networks, a value that cannot be captured for profit. The third essay is completely distinct from the network paradigm and instead studies funding rules for public universities. I show that a funding rule that depends solely on enrolment leads to "competition by franchise" and that such behavior is sometimes inefficient. I suggest instead an alternate funding rule that allows government to increase welfare without increasing spending in universities.

Download or read book Essays in the Economics of Networks written by A. N. Advani and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Essays in the Economics of Networks and Standards written by Tobias Kretschmer and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Intermediation and Leadership written by Jan-Peter Siedlarek and published by . This book was released on 2013 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis offers a contribution to the economic literature applying a networks perspective to economic issues. The focus of my thesis is the role of agents that are in particularly prominent positions within networks and how such agents affect the creation and workings of their surrounding networks. In Chapter 1 I study bargaining and exchange in a networked market with intermediation. Possibilities to trade are restricted through a network of existing relationships and traders bargain over the division of available gains from trade along feasible network routes. Using a stochastic model of bargaining, I characterise stationary equilibrium payoffs and study efficiency and the relationship between network structure and payoffs. In Chapter 2 I study the role of intermediaries in network formation. Intermediating agents can conduct "introductions" and create a connection between two agents that share them as a common neighbour. Such introductions leverage the existing structure and are formed at lower cost than non-mediated connections. I study the properties of networks formed from the perspective of myopic stability, farsighted stability and through a game of link formation. In Chapter 3, co-authored with Anja Prummer, we offer a perspective on opinion leadership in influence networks. We study the integration of immigrant communities through a model with distinct channels for social influence and skills acquisition, which act as complements in the integration process.

Download or read book Essays on Network Effects written by Yi-Nung Yang and published by . This book was released on 1997 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Network Theory and Agent Based Modeling in Economics and Finance written by Anindya S. Chakrabarti and published by Springer Nature. This book was released on 2019-10-23 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest findings on network theory and agent-based modeling of economic and financial phenomena. In this context, the economy is depicted as a complex system consisting of heterogeneous agents that interact through evolving networks; the aggregate behavior of the economy arises out of billions of small-scale interactions that take place via countless economic agents. The book focuses on analytical modeling, and on the econometric and statistical analysis of the properties emerging from microscopic interactions. In particular, it highlights the latest empirical and theoretical advances, helping readers understand economic and financial networks, as well as new work on modeling behavior using rich, agent-based frameworks. Innovatively, the book combines observational and theoretical insights in the form of networks and agent-based models, both of which have proved to be extremely valuable in understanding non-linear and evolving complex systems. Given its scope, the book will capture the interest of graduate students and researchers from various disciplines (e.g. economics, computer science, physics, and applied mathematics) whose work involves the domain of complexity theory.

Download or read book Essays in Honor of Cheng Hsiao written by Dek Terrell and published by Emerald Group Publishing. This book was released on 2020-04-15 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: Including contributions spanning a variety of theoretical and applied topics in econometrics, this volume of Advances in Econometrics is published in honour of Cheng Hsiao.

Download or read book Network Models in Economics and Finance written by Valery A. Kalyagin and published by Springer. This book was released on 2014-09-23 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using network models to investigate the interconnectivity in modern economic systems allows researchers to better understand and explain some economic phenomena. This volume presents contributions by known experts and active researchers in economic and financial network modeling. Readers are provided with an understanding of the latest advances in network analysis as applied to economics, finance, corporate governance, and investments. Moreover, recent advances in market network analysis that focus on influential techniques for market graph analysis are also examined. Young researchers will find this volume particularly useful in facilitating their introduction to this new and fascinating field. Professionals in economics, financial management, various technologies, and network analysis, will find the network models presented in this book beneficial in analyzing the interconnectivity in modern economic systems.

Download or read book Essays on the Identification and Estimation of Network Models written by Yiran Xie and published by . This book was released on 2022 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation consists of three main chapters that study social interactions in networks. In Chapter 1, I study a market with many-to-many contracts when the number of market participants increases. Many-to-many contracts allow a seller to trade with multiple buyers and a buyer to trade with multiple sellers. I focus on investigating the identification of payoff parameters through data observed from equilibrium matches in a large many-to-many matching market. In many-to-many matching markets, several issues have to be addressed: bias would arise since the outcomes are only observed when links are formed between two agents, and the maximum number of relationships an agent can enter into would possibly affect the set of stable outcomes. I show that under certain conditions, the number of firms (workers) that are willing to be matched to a specific worker (firm) grows at a rate regardless of the capacity of both sides. Furthermore, I show a correspondence between the stable matching outcomes in a many-to-many matching framework and that in a one-to-one matching framework. In Chapter 2, I conduct a structural econometric analysis of the diffusion process with players who observe their neighbors and make decisions based on their neighbors' decisions. I study the identification and estimation of diffusion processes in social and economic networks. Compared to the classic econometric diffusion literature that assumes a continuous population with a stochastic network structure, I provide a new econometric framework to analyze diffusion processes in fixed networks where Bayesian players observe their close neighbors. I demonstrate the existence of the equilibrium of the model and characterize the unique symmetric equilibrium. Based on these theoretical findings, I propose a consistent and tractable two-step estimator for payoff parameters using feasible data from a single large network. I evaluate the finite sample performance using Monte Carlo simulations. Chapter 3 applies the network diffusion model to data on the participation of a microfinance program in Indian villages to describe the impact of neighbors on individual decisions. Our model allows us to study the various network effect across different types of agents who care about their neighbors' opinions. It depends on unknown equilibrium beliefs, which specify agents' expectations about their neighbors' decisions. Using participation data from 43 villages, each including about 200 villagers, I estimate these equilibrium beliefs and the network effects.

Download or read book Essays on the Economics of Networks written by Alexander Graupner and published by . This book was released on 2020 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation contains three chapters on how economic networks affect various market situations. Broadly, they cover contracting and monopoly pricing in the presence of economic networks. The first chapter considers a principal, many agents contracting problem. Agents sit on a network of complementarities. That is, the effort of one agent affects the value of effort for those with whom he connects. Given this structure on effort, I characterize the first best contract. This contract induces efforts that reflect the agents Bonacich centrality in the symmetrized network. I then consider a variety of bilateral contracts, and compare their values for the principal. First, I consider bilateral forcing contracts. These contracts induce less effort per agent than the first best contract. Agents' effort distortions depends on their bibliographic coupling. I show that it is this novel measure that drives effort down for certain agents. Networks with high total bibliographic coupling have a large profit gap from first to second best forcing contracts. I compare these contracts to bilateral linear contracts, and show that linear contracts outperform the forcing contracts. Finally, I show that base and bonus contracts are profit maximizing for the principal, and implement first best. The second chapter considers a monopolist who introduces a new durable good to a base of consumers who are connected on a network of communication. Consumers are initially unaware of the product, and must learn about its existence through their neighbors. Each consumer who purchases informs a group of neighbors, and the information flows through consumers as a branching process. The monopolist commits to a dynamic price path on the infinite horizon. I find that though consumers are fully strategic, the monopolist finds it optimal to serve the entire consumer base infinitely often, which implies a sales structure. I then derive the optimal price path for a simplified model of two agents, and derive comparative statics. The third chapter considers a monopolist who sells to a consumer base that is largely unaware of the product. The monopolist spreads the information of the product to consumers by the past purchasers. I assume that the monopolist knows the exact network structure on which consumers live, and sets prices based off of consumers positions and the aware set of consumers. I consider three different pricing strategies. First, I consider a setting where the monopolist can price discriminate based on the consumers' network position. In this case I am able to find which consumers are important to the information flow. Consumers who are aware early get a discount, along with agents who are critical to the information flow. If there are consumers who can only be reached through one consumer purchasing, this consumer is offered a discounted price. I see that these ideas follow through to the single priced monopolist case, where prices fluctuate if many critical agents exist. Finally, I consider the optimal mechanism, where the monopolist can price discriminate based off of network position and price. In this case the monopolist can find the optimal flow of information and implement it.