  We present the dynamic propensity distribution as an explicit measure of the
degree to which the dynamics in a liquid over the time scale of structural
relaxation is determined by the initial configuration. We then examine, for a
binary mixture of soft discs in two dimensions, the correlation between the
spatial distribution of propensity and that of two localmeasures of
configuration structure: the local composition and local free volume. While the
small particles dominate the high propensity population,we find no strong
correlation between either the local composition or the local free volume and
the propensity. It is argued that this is a generic failure of purely local
structural measures to capture the inherently non-local character of collective
behaviour.
