1) Henry Wadsworth Longfellow (1807-1882) is my 7th cousin 3 times removed:
The common ancestors according to Geni.com were William Collier (1580-1671) and Jane Clark (1590-1666). My Collier ancestor is Ruth Collier according to Geni.com, but my actual Collier connection is Mary Collier (1612-1658) who married Thomas Prence. So my line back is different, but the result is the same.
2) Ralph Waldo Emerson (1803-1882) is my 7th cousin 4 times removed:
The common ancestors are David Stone (1540-1625) and Ursula Clark (1563-????), parents of Simon Stone (1586-1665) (my ancestor) and Gregory Stone (1592-1672) (Nathaniel's ancestor).
4) Henry David Thoreau (1817-1862) is my 5th cousin 5 times removed:
For all of the above, I have assumed that the Geni.com line for the famous person is correct. I don't know if that's true or not. I do know that Geni.com does not have all of my lines back to common ancestors correct, as discussed above. By doing these comparisons, I can find probably errors in Geni.com's database and perhaps be able to correct them.