  The parametrization schemes of the effective nucleon-nucleon interaction
proposed by Geramb and by Nakayama and Love are compared in their ability to
reproduce the inelastic scattering observables of polarized protons from
$^{12}$C with the excitation of the $1^+$ level with T=1. The off-shell
behavior of the effective $t$ matrix is shown to be important. Density
dependence of the effective interaction is also analyzed.
