term *reduction* noise), which includes the impact of the different frequency ranges chosen by the hounds (see lower left-hand panels of Figures \[fig:panchores\] to \[fig:katrinares\]). The magnitude of this observed scatter is larger than the characteristic internal precision on the estimated spacings. By *internal* precision, we mean the typical precision we would expect to get were one of the hounds to analyse many datasets having different shot *and* mode realization noise. For example, T. Arentoft analyzed several fully independent timeseries realizations of Boris (made by WJC), and found that the characteristic internal precision on the estimated spacings was $\sim 0.04\,\rm \mu Hz$ at $m_v=9$, and $\sim 0.20\,\rm \mu Hz$ at $m_v=11$. The observed scatter between hounds is $\approx 0.5\,\rm \mu Hz$ at both magnitudes. At the fainter magnitudes, where scatter between hounds increases, the influence of different realizations of the shot noise comes into play, and the internal precision also drops.

The quoted uncertainties should give robust estimates of the internal precision. However, it is clear from Figures \[fig:panchores\] to \[fig:katrinares\] that the quoted values cover a wide range at each $m_v$. Some of the hounds’ uncertainties were very much smaller even that the expected internal precision. In several cases, 