  This is a Reply to Comment arXiv:0707.2642 by Hof et al. on Letter
arXiv:physics/0608292 which was subsequently published in Phys Rev Lett, 98,
014501 (2007).
  In our letter it was reported that in pipe flow the median time $\tau$ for
relaminarisation of localised turbulent disturbances closely follows the
scaling $\tau\sim 1/(Re_c-Re)$. This conclusion was based on data from
collections of 40 to 60 independent simulations at each of six different
Reynolds numbers, Re. In the Comment, Hof et al. estimate $\tau$ differently
for the point at lowest Re. Although this point is the most uncertain, it forms
the basis for their assertion that the data might then fit an exponential
scaling $\tau\sim \exp(A Re)$, for some constant A, supporting Hof et al.
(2006) Nature, 443, 59. The most certain point (at largest Re) does not fit
their conclusion and is rejected. We clarify why their argument for rejecting
this point is flawed. The median $\tau$ is estimated from the distribution of
observations, and it is shown that the correct part of the distribution is
used. The data is sufficiently well determined to show that the exponential
scaling cannot be fit to the data over this range of Re, whereas the $\tau\sim
1/(Re_c-Re)$ fit is excellent, indicating critical behaviour and supporting
experiments by Peixinho & Mullin 2006.
