  The recent astronomical measurements of distant supernovae as well as other
observations indicate that our universe is presently accelerating. There are
different proposals for the explanation of this acceleration, such as the
cosmological constant $\Lambda$, decaying vacuum energy, an evolving scalar
field (quintessence), phantom energy, etc. Most of these proposals require the
existence of exotic matter with negative pressure violating the strong energy
condition. On the other hand, there have appeared many models which offer
dramatically different mechanisms for the current acceleration, in which dark
energy emerges from the gravity sector rather than from the matter sector. In
this paper, we compare the concordance $\Lambda$CDM model with the
Sahni-Shtanov brane-world models of dark energy by using the Akaike and
Bayesian information criteria. We show that new parameters in the brane model
are not statistically significant in terms of the information criteria,
although the best fit method gives an improved fit to the SNIa data, because of
the additional parameters. This is because the information criteria of model
selection compensate for this advantage by penalizing models having more free
parameters. We conclude that only new future observational data are accurate
enough to give an advantage to dark-energy models of the brane origin, i.e., a
very high-significance detection is required to justify the presence of new
parameters. In our statistical analysis both Riess et al.'s and Astier et al.'s
SNIa samples are used. For stringent constraining parameters of the models the
baryon oscillation peak (BOP) test is used.
