Download or read book Essays on Identification and Estimation of Networks written by Pedro de Souza and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Econometric Identification of Network and Choice Models with Limited Consideration written by Matthew Kelly Thirkettle and published by . This book was released on 2020 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation is comprised of two papers. In the first paper (Chapter \ref{ch2}), I obtain informative bounds on network statistics in a partially observed network whose formation I explicitly model. Partially observed networks are commonplace due to, for example, partial sampling or incomplete responses in surveys. Network statistics (e.g., centrality measures) are not point identified when the network is partially observed. Worst-case bounds on network statistics can be obtained by letting all missing links take values zero and one. I dramatically improve on the worst-case bounds by specifying a structural model for network formation. An important feature of the model is that I allow for positive externalities in the network-formation process. The network-formation model and network statistics are set identified due to multiplicity of equilibria. I provide a computationally tractable outer approximation of the joint identified region for preferences determining network-formation processes and network statistics. In a simulation study on Katz-Bonacich centrality, I find that worst-case bounds that do not use the network formation model are $44$ times wider than the bounds I obtain from my procedure. The second paper (Chapter \ref{ch3}) is concerned about learning decision makers' (DMs) preferences using data on observed choices from a finite set of risky alternatives with monetary outcomes. This chapter is coauthored with Levon Barseghyan and Francesca Molinari. We propose a discrete choice model with unobserved heterogeneity in consideration sets (the collection of alternatives considered by DMs) and unobserved heterogeneity in standard risk aversion. In this framework, stochastic choice is driven both by different rankings of alternatives induced by unobserved heterogeneity in risk preferences and by different sets of alternatives considered. We obtain sufficient conditions for semi-nonparametric point identification of both the distribution of unobserved heterogeneity in preferences and the distribution of consideration sets. Our method yields an estimator that is easy to compute and that can be used in markets with a large number of alternatives. We apply our method to a dataset on property insurance purchases. We find that although households are on average strongly risk averse, they consider lower coverages more frequently than higher coverages. Finally, we estimate the monetary losses associated with limited consideration in our application.
Download or read book Essays on Identification and Estimation of Structural Economic Models written by Shaomin Wu and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation consists of three chapters that study the identification and estimation of structural economic models. Chapter 1, "Identification and Estimation of Nonseparable Triangular Equations with Mismeasured Instruments" studies the nonparametric identification and estimation of the marginal effect of an endogenous variable X on the outcome variable Y , given a potentially mismeasured instrument variable W∗, without assuming linearity or separability of the functions governing the relationship between observables and unobservables. In order to address the challenges arising from the co-existence of measurement error and nonseparability, I first employ the deconvolution technique from the measurement error literature to identify the joint distribution of Y,X,W∗ using two error-laden measurements of W∗. I then recover the structural derivative of the function of interest and the "Local Average Response" (LAR) from the joint distribution via the "unobserved instrument" approach in Matzkin (2016). I also propose nonparametric estimators for these parameters and derive their uniform rates of convergence. Monte Carlo exercises show evidence that the estimators I propose have goodfinite sample performance. Chapter 2, "Two-step Estimation of Network Formation Models with Unobserved Heterogeneities and Strategic Interactions", characterizes the network formation process as a static game of incomplete information, where the latent payoff of forming a link between two individuals depends on the structure of the network, as well as private information on agents' attributes. I allow agents' private unobserved attributes to be correlated with observed attributes through individual fixed effects. Using data from a single large network, I propose a two-step estimator for the model primitives. In the first step, I estimate agents' equilibrium beliefs of other people's choice probabilities. In the second step, I plug in the first-step estimator to the conditional choice probability expression and estimate the model parameters and the unobserved individual fixed effects together using Joint MLE. Assuming that the observed attributes are discrete, I showed that the first step estimator is uniformly consistent with rate N−1/4, where N is the total number of linking proposals. I also show that the second-step estimator converges asymptotically to a normal distribution at the same rate. Chapter 3, "Identification and Estimation in Differentiated Products Markets Where Firms Affect Consumers' Attention" studies the nonparametric identification and estimation of a demand and supply system where firms affect consumers' consideration sets via costly marketing inputs, when market-level data is available. On the demand side, I characterize preferences and considerations nonparametrically, allowing rich heterogeneities and correlations between them. On the supply side, I characterize firms' optimal choices by a set of first-order conditions without specifying the form of the oligopoly model. The demand and supply sides form a simultaneous system of equations in the spirit of Berry and Haile (2014). I then show the identification of the system using the method proposed by Matzkin (2015). Moreover, using the variations of exclusive regressors entering preferences and considerations respectively, I separately identify features of the utility functions and the attention functions. Based on the constructive identification results, I propose nonparametric estimators of the demand, utility, and attention functions and show their asymptotic properties.
Download or read book Essays on Control written by H.L. Trentelman and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the text of the plenary lectures and the mini-courses of the European Control Conference (ECC'93) held in Groningen, the Netherlands, June 2S-July 1, 1993. However, the book is not your usu al conference proceedings. Instead, the authors took this occasion to take a broad overview of the field of control and discuss its development both from a theoretical as well as from an engineering perpective. The first essay is by the key-note speaker ofthe conference, A.G.J. Mac Farlane. It consists of a non-technical discussion of information processing and knowledge acquisition as the key features of control engineering tech nology. The next six articles are accounts of the plenary addresses. The contribution by R.W. Brockett concerns a mathematical framework for modelling motion control, a central question in robotics and vision. In the paper by M. Morari the engineering and the economic relevance of chemical process control are considered, in particular statistical quality control and the control of systems with constraints. The article by A.C.P.M. Backx is written from an industrial perspec tive. The author is director of an engineering consulting firm involved in the design of industrial control equipment. Specifically, the possibility of obtaining high performance and reliable controllers by modelling, identifi cation, and optimizing industrial processes is discussed.
Download or read book Essays in Honor of M Hashem Pesaran written by Alexander Chudik and published by Emerald Group Publishing. This book was released on 2022-01-18 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: The collection of chapters in Volume 43 Part A of Advances in Econometrics serves as a tribute to one of the most innovative, influential, and productive econometricians of his generation, Professor M. Hashem Pesaran.
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 neural network sampling methods and instrumental variables written by Lennart Hoogerheide and published by Rozenberg Publishers. This book was released on 2006 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Essays on Applied Network Theory written by Mariya Teteryatnikova and published by . This book was released on 2010 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Economic Literature written by and published by . This book was released on 2005-12 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Essays on the Econometrics of Discrete Games of Complete Information written by Li Zhao and published by . This book was released on 2016 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Next Digital Decade written by Berin Szoka and published by TechFreedom. This book was released on 2011-06-10 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Identification and Estimation of Network Formation Models written by Jun Sung Kim and published by . This book was released on 2014 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: My thesis studies identification and estimation in network formation models. First, I study what can be learned from pairwise stable networks. Pairwise stability of a network gives strong identification power when I consider the probability that the observed network is pairwise stable. I propose a semiparametric maximum score estimator which is simple and computationally feasible. I apply the empirical model to social and economic networks in rural India, and find homophily patterns in village networks. Second, I propose a structural model of multigraph formation, where 1) individuals determine multiple types of links simultaneously; 2) all networks interact with each other; and 3) one or more networks are endogenous but not simultaneous. I extend the notion of pairwise stability to a multigraph, and show that the structural model is equivalent to a multinomial choice model. The presence of endogenous but not simultaneous networks is a source of an incomplete econometric model. Relying on partially identified econometric models, I characterize the sharp identification region of parameters by a finite set of moment inequalities. I apply the model to village networks and find that friendship affects risk sharing and favor exchange networks in the same direction. The last chapter studies an empirical model of network formation in the U.S. airline industry and investigates the size of network externalities. I assume that each airline builds a network that satisfies a weak notion of stability. That is, no airlines want to deviate from their current networks by a single route change. In this framework, I can use an entry game to investigate the airline industry and include network measures in the profit function to estimate network externalities. I find that when I control for the number of one-stop flights the effect of hub-size is larger than the case without considering one-stop flights.
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 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 Production Function Estimation written by Mert Demirer and published by . This book was released on 2020 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first chapter develops a new method for estimating production functions with factor-augmenting technology and assesses its economic implications. The method does not impose parametric restrictions and generalizes prior approaches that rely on the CES production function. I first extend the canonical Olley-Pakes framework to accommodate factor-augmenting technology. Then, I show how to identify output elasticities based on a novel control variable approach and the optimality of input expenditures. I use this method to estimate output elasticities and markups in manufacturing industries in the US and four developing countries. Neglecting labor-augmenting productivity and imposing parametric restrictions mismeasures output elasticities and heterogeneity in the production function. My estimates suggest that standard models (i) underestimate capital elasticity by up to 70 percent (ii) overestimate labor elasticity by up to 80 percent. These biases propagate into markup estimates inferred from output elasticities: markups are overestimated by 20 percentage points. Finally, heterogeneity in output elasticities also affects estimated trends in markups: my estimates point to a much more muted markup growth (about half) in the US manufacturing sector than recent estimates. The second chapter develops partial identification results that are robust to deviations from the commonly used control function approach assumptions and measurement errors in inputs. In particular, the model (i) allows for multi-dimensional unobserved heterogeneity,(ii) relaxes strict monotonicity to weak monotonicity, (iii) accommodates a more flexible timing assumption for capital. I show that under these assumptions production function parameters are partially identified by an 'imperfect proxy' variable via moment inequalities. Using these moment inequalities, I derive bounds on the parameters and propose an estimator. An empirical application is presented to quantify the informativeness of the identified set. The third chapter develops an approach in which endogenous networks is a source of identification in estimations with network data. In particular, I study a linear model where network data can be used to control for unobserved heterogeneity and partially identify the parameters of the linear model. My method does not rely on a parametric model of network formation. Instead, identification is achieved by assuming that the network satisfies latent homophily - the tendency of individuals to be linked with others who are similar to themselves. I first provide two definitions of homophily: weak and strong homophily. Then, based on these definitions, I characterize the identified sets and show that they are bounded under weak conditions. Finally, to illustrate the method in an empirical setting, I estimate the effects of education on risk preferences and peer effects using social network data from 150 Chinese villages.
Download or read book The Econometrics of Networks written by Áureo de Paula and published by Emerald Group Publishing. This book was released on 2020-10-19 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Showcasing fresh methodological and empirical research on the econometrics of networks, and comprising both theoretical, empirical and policy papers, the authors in this volume bring together a wide range of perspectives to facilitate a dialogue between academics and practitioners for better understanding this groundbreaking field.
