Strengthening Instrumental Variables Through Weighting

Strengthening Instrumental Variables through Weighting

Instrumental variable (IV) methods are widely used to deal with the issue of unmeasured confounding and are becoming popular in health and medical research. IV models are able to obtain consistent estimates in the presence of unmeasured confounding, but rely on assumptions that are hard to verify and often criticized. An instrument is a variable that influences or encourages individuals toward ...

Regression and Weighting Methods for Causal Inference Using Instrumental Variables

Recent researches in econometrics and statistics have gained considerable insights into the use of instrumental variables (IVs) for causal inference. A basic idea is that IVs serve as an experimental handle, the turning of which may change each individual’s treatment status and, through and only through this effect, also change observed outcome. The average difference in observed outcome relati...

Ecological Inferencewith Instrumental Variables

This note observes that instrumental variables techniques are useful not only for estimating causal effects, but that they simultaneously solve the ecological inference problem. ∗Correspondence can be addressed to the author at MEDS Department, Kellogg School of Management, 2001 Sheridan Rd, Evanston, IL 60208, or by email: [email protected]. The ecological inference problem i...

Instrumental variables and inverse probability weighting for causal inference from longitudinal observational studies.

Inferring causal effects from longitudinal repeated measures data has high relevance to a number of areas of research, including economics, social sciences and epidemiology. In observational studies in particular, the treatment receipt mechanism is typically not under the control of the investigator; it can depend on various factors, including the outcome of interest. This results in differenti...

Mediating Instrumental Variables