  We consider three- and four-dimensional pseudo-Riemannian generalized
symmetric spaces, whose invariant metrics were explicitly described in [15].
While four-dimensional pseudo-Riemannian generalized symmetric spaces of types
A, C and D are algebraic Ricci solitons, the ones of type B are not so. The
Ricci soliton equation for their metrics yields a system of partial
differential equations. Solving such system, we prove that almost all the
four-dimensional pseudo-Riemannian generalized symmetric spaces of type B are
Ricci solitons. These examples show some deep differences arising for the Ricci
soliton equation between the Riemannian and the pseudo-Riemannian cases, as any
homogeneous Riemannian Ricci soliton is algebraic [21]. We also investigate
three-dimensional generalized symmetric spaces of any signature and prove that
they are Ricci solitons.
