Obviously dwarf galaxies are more common than large galaxies. Personally I think that the really tiny galaxies are not so interesting. Galaxies smaller than half the size of the Small Magellanic Cloud should perhaps not be counted here.
How dominant are the large galaxies when it comes to the number of stars they contain? How many galaxies like the Fornax Dwarf would it take to "fill" the Milky Way with the required number of stars (that is, how many more stars are there in the Milky Way than in the Fornax Dwarf)? And how many galaxies like the Fornax Dwarf would it take to provide the total mass of the Milky Way?
Imagine a kind of galactic roulette wheel. Each number of this wheel represent different types of galaxies. There are the monstrously large elliptical galaxies like M 87, although they would be rare. There are the considerably smaller elliptical galaxies, and I'm sure there are several of those in the Virgo cluster. There are the quite small elliptical galaxies like NGC 205. There are the really large spiral galaxies like M 88 and NGC 1961, which are very rare. There are the much smaller spiral galaxies like M 33. And there are galaxies like the Milky Way.
Let's play the roulette in two different ways. In the first round, each type of galaxy is assigned a one or more numbers, depending on how common this galaxy type is. Galaxies like M 87 would certainly get no more than one number, but galaxies like NGC 205 might get so many numbers that there wouldn't be many numbers left for the spirals! Perhaps we need a larger roulette wheel with more numbers?
If we play the roulette wheel this way, how likely is it, statistically speaking, that "our" number (corresponding to spiral galaxies the size of the Mily Way) would "win" the round?
Let's play the roulette in a different way. Now let's consider the total number of stars in the low-z universe and consider what kind of galaxy stars are more likely to find themselves in. How many of the stars of the moderately local universe are inside galaxies like M 87? How many stars are inside galaxies like NGC 205? How many stars are inside galaxies like M 88 and NGC 1961? How many stars are inside galaxies like M 33? And how many stars are inside spiral galaxies more or less the size of the Milky Way?
To put it differently, how ordinary is the Milky Way in the moderately low-z universe? And how likely is it, statistically speaking, that the Sun would be found inside a spiral galaxy the size of the Milky Way?
How likely is it that the Milky Way would win?
Ann