Thanks for this.What markod says. Also, ADMIXTURE is a quite rough approach to genetic mixture, especially if you mix older populations with modern day populations. Also, to fully appreciate what it states you need to weigh in other K values as well. ADMIXTURE goes a bit like this: When *forced* to be modeled as combination of two of the provided samples how would they look (That is K=2), and when *forced* to be modeled as a combination of three samples (K=3), etc etc. Afterwards the statistically best fit is chosen, if run in an unsupervised mode. Even in the unsupervised case a lot of individual samples will simply be a forced bad fit.
The tools that Reich labs created (f3stats, D-stats and ADMIXTURE) are available but rather complicated to use. Also, you'd probably need the full samples which take up a huge amount of disk space for those, but if you choose that path and are willing to experience a steep learning curve you can download it here.
Eurogenes Davidski provides a simpler tool called nMonte, created by Huijbrechts, (more explanation here) that allows modeling on the basis of pre-calculated PCA values. It's conclusions are consistently similar to qpAdm of the Reich lab tools. You have to install "R", though.
Does it produce substantially different results, do you know? And if so, what are they?
The striking thing about the autosomal analysis I have carried out is that it provides pretty similar results to yDNA and mtDNA analysis that I have undertaken using different methodologies.