Back in 2011 when I started working with the Bührer dataset it was clear to me that all the emigrated Bührers are “family”, i.e. are more or less closely related to me. A first glimpse at the map’s family tree in 2015 showed that this assumption is somewhat shaky – most of the emigrated Bührers are rather distant relatives.
A renewed look (see above) gives a more precise picture: relative to me (generation and degree of relationship = 0) the closest emigrated relative is Michael Bührer (generation = 5, degree of relationship = 6) who directly descends from the 10th generation of my direct line of ancestors. The degree of relationship of US persons (living or dead) ranges from 6th to 11th degree. Not that related after all…
Note that indicated degree of relationship according to my calculation (I didn’t find an authoritative source on how to calculate it) doesn’t increase in direct descendancy unless the generation is below 0.