  The cosmic acceleration is one of the most significant cosmological
discoveries over the last century. The two categories of explanation are exotic
component (dark energy) and modified gravity. We constrain the two types of
model by a joint analysis with perturbation growth and direct $H(z)$ data.
Though the minimal $\chi^2$ of the $\Lambda$CDM is almost the same as that of
DGP, in the sense of consistency we find that the dark energy ($\Lambda$CDM)
model is more favored through a detailed comparison with the corresponding
parameters fitted by expansion data.
