The norm E has to be minimized from the point
of view of the definition of the optimization problem:
the objective function is E and the design variables
are related to the ordering in the sampling
scheme (Table 1). It is well known that the deterministic
optimization techniques and the simple stochastic
optimization approaches can very often fail
to find the global minimum. Such a technique fails
in some local minimum and then there is no chance
to escape from it and to find the global minimum. It
can be intuitively predicted that in our problem we
are definitely facing the problem with a multiple local
minima. Therefore we need to use the stochastic
optimization method which works with some probability
of escaping from the local minimum. The
simplest form is the two-member evolution strategy
which works in two steps: Mutation and selection.