\documentclass[11pt]{article} \setlength{\oddsidemargin}{0.0truein} \setlength{\evensidemargin}{0.0truein} \setlength{\textwidth}{6.5truein} \setlength{\topmargin}{0.0truein} \setlength{\textheight}{9.0truein} \setlength{\headsep}{0.0truein} \setlength{\headheight}{0.0truein} \setlength{\topskip}{10.0pt} \setlength{\parskip}{5mm} \usepackage{url} \begin{document} \begin{center} \textbf{\textsc{STANFORD UNIVERSITY}}\\[5pt] \textbf{\textsc{DEPARTMENT OF STATISTICS}}\\[5pt] \Large{\textbf\textsc{{DEPARTMENTAL SEMINAR}}} \end{center} \begin{center} 4:15 p.m., Tuesday, February 7, 2006\\ Sequoia Hall Room 200\\ (Cookies at 3:45 in 1st Floor Lounge) \end{center} \begin{center} \textsl{Tyler VanderWeele} \\ Department of Biostatistics\\ Harvard School of Public Health\\ \end{center} \begin{center} \textbf{Directed Acyclic Graphs and Monotonic Effects} \end{center} \noindent The directed acyclic graph causal framework has been used with increasing frequency to address concerns of confounding in a variety of research settings. The directed acyclic graph framework allows for the representation of causal and counterfactual relations amongst variables; the estimation of causal effects through the g-formula; the detection of independencies through the d-separation criteria; and the implementation of algorithms to determine whether conditioning on a particular set of variables, or none at all, is sufficient to control for confounding as well as algorithms which identity such a set of variables. By incorporating notions of monotonic effects, the directed acyclic graph casual framework can be extended so as to allow for the graphical representation of monotonic effects on causal directed acyclic graphs through signed edges; the use of monotonic effects to determine the sign of the causal effect of an intervention in the presence of intermediate variables; the use of monotonic effects to develop rules governing montonicity and covariance; and finally the use of monotonicity to determine the sign of the bias when control for confounding is inadequate. \end{document}