Department of Statistics, UCLA

A causal claim is any assertion that invokes causal relationships between variables, for example, that a drug has a certain effect on preventing a disease. Causal claims are established through a combination of data and a set of causal assumptions called a "causal model." A claim is robust when it is insensitive to violations of some of the causal assumptions embodied in the model. This paper gives a formal definition of this notion of robustness, and establishes a graphical condition for quantifying the degree of robustness of a given causal claim. Algorithms for computing the degree of robustness are also presented.