doi:10.1017/pan.2018.46, Published by Cambridge University Press, 18 December 2018
In the above publication (Hainmueller et al. Reference Hainmueller, Mummolo and Xu2018), the reference for Grimmer et al. (2014) was incomplete. The complete citation is shown below:
Grimmer, Justin, Solomon Messing, and Sean J. Westwood. 2014. Estimating heterogeneous treatment effects and the effects of heterogeneous treatments with ensemble methods. Political Analysis 25(4):413–434.
The authors apologize for this error.