How many X's do you know'' surveys - Columbia University

Overview
Social and political polarization
Background: how many people do you know?
Learning from “How many X’s do you know” surveys
Next
3 models
Fitting our model
Results: how many people do you know?
Results: group sizes and overdispersions
Confidence building and model extensions
Gibbs-Metropolis algorithm: updating hyperparameters
◮ Update µ α ∼ N ( 1∑ n
n i=1 α i, 1 n σ2)
◮ Update σα 2 ∼ Inv-χ 2 ( n−1, 1 ∑ n
n i=1 (α i − µ α ) 2)
◮ Similarly with µ β , σ β
◮ Renormalize to identify the α’s and β’s . . .
Gelman, DiPrete, Salganik, Teitler, Zheng
Studying polarization using surveys