  Breakjunction experiments allow investigating electronic and spintronic
properties at the atomic and molecular scale. These experiments generate by
their very nature broad and asymmetric distributions of the observables of
interest, and thus a full statistical interpretation is warranted. We show here
that understanding the complete distribution is essential for obtaining
reliable estimates. We demonstrate this for Au atomic point contacts, where by
adopting Bayesian reasoning we can reliably estimate the distance to the
transition state, $x{\ddag}$, the associated free energy barrier,
${\Delta}G{\ddag}$, and the curvature $\nu$ of the free energy surface.
Obtaining robust estimates requires less experimental effort than with previous
methods, fewer assumptions, and thus leads to a significant reassessment of the
kinetic parameters in this paradigmatic atomic-scale structure. Our proposed
Bayesian reasoning offers a powerful and general approach when interpreting
inherently stochastic data that yield broad, asymmetric distributions for which
analytical models of the distribution may be developed.
