Date:
Location:
This Week's Speaker
Naijia Liu (Department of Government), "Synthetic Control Method with Pre-treatment Outcomes Missing" (joint w/ Sooahn Shin and Soichiro Yamauchi)
Abstract
The synthetic control method (SCM) is commonly used in social science research to estimate treatment effects. It involves creating a synthesized control unit for the treated unit in observational studies. The quality of this synthesized control unit is influenced by factors like the number of pretreatment periods and missing values. Many empirical datasets, particularly those with a panel structure, often encounter issues with missing values. This project studies the impact of missing values on SCM and provides theoretical guidance to the potential bias. We formulate SCM with missing data in a vertical regression perspective. Under such setting, missing values can be deemed as omitted variables. We show that the bias of the ATT is decomposed into (1) weight of the missing unit for constructing the synthetic control and (2) the imbalance between the missing units and the weighted observed donor units. Building on these result, We propose a sensitivity analysis for SCM with pretreatment outcomes missing not at random. To illustrate the method in practice, we revisit a previous study that examines the impact of Taiwan's expulsion from the International Monetary Fund (IMF) in 1980 on its precautionary international reserves using the SCM.
The Applied Statistics Workshop (Gov 3009) meets all academic year, Wednesdays, 12pm-1:30pm, in CGIS K354. This workshop is a forum for advanced graduate students, faculty, and visiting scholars to present and discuss methodological or empirical work in progress in an interdisciplinary setting. The workshop features a tour of Harvard's statistical innovations and applications with weekly stops in different fields and disciplines and includes occasional presentations by invited speakers.
More information is available at the Gov 3009 website: https://projects.iq.harvard.edu/applied.stats.workshop-gov3009
All interested Harvard affiliates are invited to attend.