A Structural Pairwise Network Model with Individual Heterogeneity
2016/11/08
研討會日期 : 2016-11-08
時間 : 14:30
主講人 : Professor Zhentao Shi
主持人 : Professor Jen-Che Liao
地點 : Conference Room B110
演講者簡介 : Professor Shi received his Ph.D. in Economics from Yale University in 2014. He is currently an Assistant Professor at the Department of Economics, Chinese University of Hong Kong. His research fields are Econometric Theory and Applied Econometrics.
演講摘要 : Pairwise binary regressions are widely used to predict network links by each pair of agents' observed attributes. We propose a new structural pairwise network model based on individual utility maximization. In this model, the econometrician, as an outsider, witnesses a link if and only if both agents prefer it, while the agent is willing to create a bond with a peer if he or she gains positive individual utility from the potential connection. Besides observed personal attributes, unobservable individual heterogeneity enters the random utility as an additive fixed effect. The fixed effects enhance the applicability of the model, but impose technical challenges as they are buried in nonlinear functions. To identify and estimate the model, we exploit the special panel-data structure. In a network of n individuals, we can view one's linking outcomes to all the n-1 peers as a within-group observation, so that the network provides n overlapping groups. We treat each fixed effect term as an unknown nuisance parameter. Under a distributional assumption about the link-specific idiosyncratic shock, we establish consistency and asymptotic distribution for the maximum likelihood estimator of the common parameter. We apply this estimator to study the determinants of gift exchange in a network of village households in China.
