Published online by Cambridge University Press: 01 October 2019
For a Brownian bridge from 0 to y, we prove that the mean of the first exit time from the interval
$\left( -h,h \right),h>0$
, behaves as
${\mathrm{O}}(h^2)$
when
$h
\downarrow 0$
. Similar behaviour is also seen to hold for the three-dimensional Bessel bridge. For the Brownian bridge and three-dimensional Bessel bridge, this mean of the first exit time has a puzzling representation in terms of the Kolmogorov distribution. The result regarding the Brownian bridge is applied to provide a detailed proof of an estimate needed by Walsh to determine the convergence of the binomial tree scheme for European options.