A Review of Statistical Methods for Handling Nonignorable Missing Data using Instrument Approach
利用工具变量处理不可忽略缺失数据的统计方法综述
Nonignorable missing data, where the probability of missingness depends on unobserved values, presents a significant challenge in statistical analysis. Traditional methods often rely on strong parametric assumptions that are difficult to verify and may lead to biased estimates if misspecified. Recent advances have introduced the concept of a nonresponse instrument or shadow variable as a powerful tool to enhance model identifiability without requiring full parametric…