“…The first example is taken from [18]. In this case the equation of motion is given by equations (6) and (7) 3 to a certain extent dominates the termaY\ in equation (9), it was decided, in accordance with the introductory discussion of this section, to investigate the velocity, Y 2 , and hysteretic 'force', Y 3 , separately by replacing equation (9) by the 'decoupled' equation (14) By this, the problem of calculating estimates of the stationary PDFs of Y 2 and Y 3 is reduced to a 2D problem, which is much easier to handle computationally than a full 3D calculation.…”