Let
be a commutative ring.
For any projective
-module
of constant
rank
with a trivialization of its determinant, we define a generalized
Vaserstein symbol on the orbit space of the set of epimorphisms
under the action of the group of elementary automorphisms of
, which
maps into the elementary symplectic Witt group. We give criteria for the surjectivity and
injectivity of the generalized Vaserstein symbol and deduce that it is an isomorphism if
is a regular Noetherian ring
of dimension
or a regular
affine algebra of dimension
over a perfect field
with
and
.