5 papers
Semiparametric fractional imputation using Gaussian mixture models for handling multivariate missing data
Hejian Sang, Jae Kwang Kim
Item nonresponse is frequently encountered in practice. Ignoring missing data can lose efficiency and lead to misleading inference. Fractional imputation is a frequentist approach…
A Profile Likelihood Approach to Semiparametric Estimation with Nonignorable Nonresponse
Hejian Sang, Kosuke Morikawa
Statistical inference with nonresponse is quite challenging, especially when the response mechanism is nonignorable. The existing methods often require correct model specifications…
Bayesian Sparse Propensity Score Estimation for Unit Nonresponse
Hejian Sang, Gyuhyeong Goh, Jae Kwang Kim
Nonresponse weighting adjustment using propensity score is a popular method for handling unit nonresponse. However, including all available auxiliary variables into the propensity…
Adaptive Stochastic Gradient Langevin Dynamics: Taming Convergence and Saddle Point Escape Time
Hejian Sang, Jia Liu
In this paper, we propose a new adaptive stochastic gradient Langevin dynamics (ASGLD) algorithmic framework and its two specialized versions, namely adaptive stochastic gradient (…
An approximate Bayesian inference on propensity score estimation under unit nonresponse
Hejian Sang, Jae Kwang Kim
Nonresponse weighting adjustment using the response propensity score is a popular tool for handling unit nonresponse. Statistical inference after the nonresponse weighting adjustme…