  We study an asymptotic limit of Vlasov type equation with nonlocal
interaction forces where the friction terms are dominant. We provide a
quantitative estimate of this large friction limit from the kinetic equation to
a continuity type equation with a nonlocal velocity field, the so-called
aggregation equation, by employing $2$-Wasserstein distance. By introducing an
intermediate system, given by the pressureless Euler equations with nonlocal
forces, we can quantify the error between the spatial densities of the kinetic
equation and the pressureless Euler system by means of relative entropy type
arguments combined with the $2$-Wasserstein distance. This together with the
quantitative error estimate between the pressureless Euler system and the
aggregation equation in $2$-Wasserstein distance in [Commun. Math. Phys, 365,
(2019), 329--361] establishes the quantitative bounds on the error between the
kinetic equation and the aggregation equation.
