- the Villabruna cluster shows a strong correlation with Villabruna affinity simply because the K7 is pretty good at estimating proportions of Villabruna-related admixture and, at the same time, Villabruna is an excellent reference sample for Villabruna-related affinity in Western Eurasians - the Basal-rich cluster shows a strong inverse correlation with AG3 affinity because, paradoxically, AG3 is a fairly poor reference for AG3-related admixture in most Western Eurasians, thereby acting as a pretty good reference for overall Basal Eurasian-free forager ancestry (note that the correlation only breaks down somewhat for samples unusually rich in AG3-related ancestry compared to their neighbors, like those from the Bronze Age steppe and Caucasus) - the Basal-rich cluster shows a fairly poor inverse correlation with Villabruna affinity because, again, as per above, and also somewhat paradoxically, Villabruna is an excellent proxy for Villabruna-related admixture in Western Eurasians, thereby forcing groups with unusually high Villabruna-related admixture and affinity well above the diagonal line - the AG3-MA1 cluster shows a fairly poor correlation with AG3 affinity simply because, as per above, AG3 is a fairly poor reference for AG3-related admixture in Western Eurasians, and especially West Central Asians, thereby forcing them well below the diagonal lineUpdate 17/08/2016: And Matt's explanation is in the comments here, along with the graphs below. The Basal-rich K7
Monday, August 15, 2016
Basal-rich K7 vs D-stats: the puzzle
It's interesting that, as per the graphs below, the K7 Villabruna cluster shows an awesome correlation with Villabruna affinity. At the same time, the K7 Basal-rich cluster shows an awesome inverse correlation with AG3 (aka AfontovaGora3) affinity. Conversely, the K7 Basal-rich cluster shows a much poorer inverse correlation with Villabruna affinity, and the K7 AG3-MA1 cluster shows a much poorer correlation with AG3 (aka. AfonovaGora3) affinity. Why is that? Anyone know? If you think you do, please post your answer in the comments. I already know why and shall reveal the answers shortly. The relevant datasheet is available here.