It is fairly common for black Americans to share the last name of presidents, eg Washington, Jefferson, or Roosevelt. Why is this? I assume it is due to slavery, when many of the presidents were large slave owners, and the name has been passed down. If that's the case, though, why would some names like Roosevelt be common, and why are some presidential names that should have owned slaves be uncommon, such as Madison or Adams?
It isn't actually related to the owners necessarily, and the number of slaves various presidents owned wouldn't come close to accounting for the huge number of African Americans today with their last names; to my knowledge the Roosevelt family never even owned slaves, aside from perhaps some house slaves in the earlier generations (they were a prominent New York family).
It has to do more with the fact that they were basically able to choose their own names. Before emancipation some slaves would have given themselves a last name, though they wouldn't be legally identified by it until afterwards; after the Civil War, they needed to give themselves last names. The names of various founding fathers were seen to represent liberty, freedom, etc. and were thus fairly popular among a group proud of their new freedom.