results from all five studies, rather than to retain merely a smaller sample composed of the most recent or most accurate results. One advantage of this it that by comparing the results from the different studies we are able to put firm limits on various kinds of potential systematic uncertainties.

Distances {#ss:dist}
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It is important for our study to use a set of galaxy distances that is as accurate and homogeneous as possible. For this we follow the example of G03 and C06 by using the compilation of Tonry [[et al. ]{}]{}(2001, hereafter T01). They obtained distances to 300 nearby galaxies, mostly of early type, using the surface brightness fluctuation (SBF) method. We removed from our initial sample of 81 total galaxies in vdM91, M98, K00, G03 and C06 the 17 galaxies that are not part of the T01 sample. We rejected two more galaxies (M31 and NGC 4594) because they are not early-type galaxies (which we define here as Hubble type $T <
0$) and two other galaxies (NGC 3384 and NGC 7332) for the reasons discussed in Section \[ss:dispersions\]. Table \[t:local\] lists the final sample of 60 galaxies and includes for each galaxy, among other things, the 