Two responses have now been published to the Vandenbroucke-Broadbent-Pearce paper on Potential Outcomes in IJE (Jan 2016).
We have replied to these letters (open access).
As well as this exchange of letters, the IJE has asked for some fuller commentaries on our paper, as well as our response to these commentaries. The exchange is developing in an extremely useful way, in my view, and I look forward to being able to share the next “round”, perhaps later this year.
Our original paper is here.