We have computed the Band Area Ratio (BAR) and Band I Center parameters, following the method by Cloutis et al. (1986) and Gaffey et al. (1993) for all the existent visible and near-infrared spectra of near-Earth asteroids (NEAs), main belt asteroids (MBs) and meteorites (Duffard et al.2005). For the NEAs we have grouped observations from NEOSS (de León et al. 2007), SINEO (Lazzarin et al. 2005) and SMASS (Bus & Binzel, 2002b ; http://smass.mit.edu/minus.html) databases, with a total of 76 objects. In the case of MBs, we have joined visible spectra from SMASS database with near-infrared spectra from 52-color database when available, using also MB objects observed during the runs of the NEOSS. A total of 71 complete spectra of main belt asteroids have been studied. Errors were also computed for both parameters. From a first comparison of both plots, there seems to be a lack of NEAs through the diagonal of the graph (from bottom-left to upper-right), while this region is quite well filled in the case of MB objects. Besides, there are much more objects located near the olivine-rich region in the case of MB asteroids than for NEAs. Those regions in the plot were defined based on meteorite samples, so if meteorites come directly from the NEAs, then the two poupulations must be compatible. We will show that this is the case. We will discuss these and other differences between the distribution of both populations in the spectral parameters space, considering questions as the size of the bodies or the completeness of the different databases available, as well as the mineralogical implications that could be driven from this kind of plots.