When estimating average treatment impact for a multisite randomized trial, recent literature (see Bloom et al. (2017)) has suggested using the so-called FIRC (Fixed Intercept, Random Coefficient) model. There are some technical details that make fitting this model slightly tricky in R; this post talks through these …

A shady figure presents you with a game. They have a deck of cards numbered 1, 2, 3, or 4, the exact distribution of which you do not know. They randomly shuffle and separate the deck into two equally sized piles, facedown, and after checking the piles for themselves, reveal some cards from each. From the first set: 4, …

You’ve taken the leap, and you wrote a manuscript using R Markdown. Good job! I support your endeavor, especially as it is a good practice for reproducible research. You’ve finished your work, and you want to submit your manuscript for publication. Unfortunately, the journal has various style and formatting …

Does becoming President of the United States cause you to age faster than you would have otherwise, if you had not become President? Media sources have claimed that presidents age more quickly while in office. The British tabloid The Daily Mail asserted “American presidents age TWICE as fast while in office” (Daily …

An annoyance (for me) is when I want to compare different groups portrayed in a nice plot that is kind enough to provide error bars. Consider a hypothetical data collection effort where we have 5 groups and are looking at the mean outcome of these 5 groups. Our estimated means and standard deviations are as follows: …

Once an analysis is in, we need to think carefully about how to talk about our results. Statistics is about inference, about capturing the uncertainty in our findings given limitations of our data and estimation error. We want the reader to quickly assess how seriously to take an estimated difference, and we want to …

This is a live document that is subject to updating at any time. Introduction This document, the first of a three part series, is an introduction to matching in R using the optmatch and RItools packages. We focus on unit-to-unit matching, as opposed to other recent approaches that focus on obtaining overall balance in …