This paper concerns the correspondence matching of ambiguous feature sets e
xtracted from images. The first contribution made in this paper is to exten
d Wilson and Hancock's Bayesian matching framework (Wilson and Hancock, IEE
E Trans. Pattern Anal. Mach. Intell. 19 (1997) 634-648) by considering the
case where the feature measurements are ambiguous. The second contribution
is the development of a multimodal evolutionary optimisation framework whic
h is capable of simultaneously producing several good alternative solutions
. Previous multimodal genetic algorithms have required additional parameter
s to be added to a method which is already over-parameterised. The algorith
m presented in this paper requires no extra parameters: solution yields are
maximised by removing bias in the selection step, while optimisation perfo
rmance is maintained by a local search step. This framework is in principle
applicable to any multimodal optimisation problem where local search perfo
rms well. An experimental study demonstrates the effectiveness of the new a
pproach on synthetic and real data. (C) 2000 Pattern Recognition Society. P
ublished by Elsevier Science Ltd. All rights reserved.