in Wild et al. (2016), as briefly outlined in Section \[sec:masses\].

The size–mass relations show the expected trends for star-forming and passive galaxies, consistent with previous studies (e.g. Daddi et al. 2005; Trujillo et al. 2006; van Dokkum et al. 2008; van der Wel et al. 2014; McLure et al. 2013). On average, passive galaxies appear significantly more compact than star-forming galaxies of equivalent stellar mass, but show a steeper size–mass relation, leading to convergence at the highest masses (M$_{\ast} \sim 10^{11.5}
~$M$_{\sun}$). Intriguingly, we find that post-starburst galaxies at this epoch are also extremely compact; they are comparable in size to the established passive galaxies, with evidence that they are smaller on average at high mass (M$_{\ast}> 10^{10.5} ~$M$_{\sun}$). These trends are apparent with the large ground-based sample and with the smaller CANDELS sample.

We performed a bootstrap analysis as a simple test of significance, randomly sampling the (ground-based) populations within each mass bin, with replacement. For the 4 bins above $10^{10.5} ~$M$_{\sun}$, the fraction of the resampled populations in which the passive galaxies show mean sizes equal to (or smaller than) the mean of the PSB population are  $0.07$, $5\times10^{-5}$, $1.2\times 10^{-4}$, $4\times10^{-5}$ (low to high mass, respectively). 