I estimate that there are 300,000 Ferguson and variants worldwide with slightly more than half of these resident in the US. We only have 250 participants in project which with 150,000 men to sample seems ridiculously small. However, I estimate further that back about 1600 there were only 5,000 Ferguson and 80% of these were in Scotland. If you assume that an average household of 5 then that equates to 1,000 heads of household as progenitors of all 300,000 Ferguson alive today. See http://dna.cfsna.net/Demographics.htm One number in particular that I struggle to estimate is how many of those 1,000 heads of household would we call related to one another. If that number is one in five then then I am down to only 200 earliest known ancestors that need be tested to characterize today's population of Ferguson. A reasonable sample size at least seems attainable. In our project we have about 20 different groupings of Ferguson each sharing their own ancestor about 800 years ago; 400 years the time back from present to our 1600s progenitors and another 400 years as a TMRCA for the 1600s progenitors accounting for the one in five as above. The 20 different groups referred to account for about half our participants, the remainder fall in small groups or don't match other participants. Relative to 200 earliest known ancestors our sample size is still small but at least not ridiculously so. Am I on track?

There are so many factors that can affect how many progenitors any given surname has, it's difficult to predict how many there will actually turn out to be. Personally, I go into this kind of research with no expectations, and just let the data tell me the story. It's a patience I've learned, I guess, from being a scientist (now retired). Having expectations can lead to bias, and trying to make interpretations from too little data is futile, so I've learned to suppress the inclination to do either. I know that's not an exciting answer, but the lesson learned by every grad student is that it takes more data than you ever thought to really prove something. There is also a sampling issue here that is important for us: until your rarest group is represented by at least three individuals, there is a high probability that you have not found all groups. Now, the assumption here is that you are sampling a population randomly, which a surname project may not be doing. That is, I have no idea whether the FERGUSONs being tested are a random sample of FERGUSONs, or not. But, I think it's safe to say (and setting aside the issue of NPEs): As long as you have any FERGUSONs in your project who have no match, you can assume you have not, possibly remotely not, tested all the lineages. Rather than just sitting back and waiting for enough FERGUSONs to randomly join the project, one thing you can do to speed progress is to make a list of known FERGUSON immigrants to the U.S., then make it your goal to find and test at least one patrilineal descendant of each. The next goal would be to test a second one, to be certain the first doesn't have an NPE -- and if the first two don't match, to test a third, for the same reason. Of course, you would love to test FERGUSONs in Scotland, but if you're having as much trouble as I am bringing Europeans into your project, that's not really an option. Hope this helps, Diana > -----Original Message----- > From: y-dna-projects-bounces@rootsweb.com [mailto:y-dna-projects- > bounces@rootsweb.com] On Behalf Of Colin Ferguson > Sent: Friday, September 10, 2010 11:50 AM > To: Y-DNA-PROJECTS@rootsweb.com > Subject: [Y-DNA-projects] Sample Size > > I estimate that there are 300,000 Ferguson and variants worldwide with slightly more > than half of these resident in the US. We only have 250 participants in project which > with 150,000 men to sample seems ridiculously small. However, I estimate further > that back about 1600 there were only 5,000 Ferguson and 80% of these were in > Scotland. If you assume that an average household of 5 then that equates to 1,000 > heads of household as progenitors of all 300,000 Ferguson alive today. > See http://dna.cfsna.net/Demographics.htm > > One number in particular that I struggle to estimate is how many of those 1,000 > heads of household would we call related to one another. > If that number is one in five then then I am down to only 200 earliest known > ancestors that need be tested to characterize today's population of Ferguson. A > reasonable sample size at least seems attainable. > > In our project we have about 20 different groupings of Ferguson each sharing their > own ancestor about 800 years ago; 400 years the time back from present to our > 1600s progenitors and another 400 years as a TMRCA for the 1600s progenitors > accounting for the one in five as above. The 20 different groups referred to account > for about half our participants, the remainder fall in small groups or don't match > other participants. Relative to 200 earliest known ancestors our sample size is still > small but at least not ridiculously so. > > Am I on track? > > ------------------------------- > To unsubscribe from the list, please send an email to Y-DNA-PROJECTS- > request@rootsweb.com with the word 'unsubscribe' without the quotes in the subject > and the body of the message