This is the current status of the family tree of Q-L804 based on the data at YFull. Branch length in years I have estimated with the Ape package in R using maximum likelihood and the “strikt model”. The rightmost codes refer to actuall test persons (YFxxxxx). YF02661 is a decendant of Erik Ersson in Knaften. YFulls version of the tree can be found at: https://www.yfull.com/tree/Q-L804/.
The idea of maximum likelihood here is to choose the branch lengh that gives the most likely “pedigree” given the observed number of SNPs at every branch. The mean time to a new SNP is assumed to be 144.41 years, constant over all branches. (If this assumption hold it means that other methods of calculating TMRCA, such as YFulls own is less likely to be true than this method). This makes also the strikt model suiatable. Some background for these choises can be found in:
Tagankin, Vladimir, and Vadim Urasin. “Defining a New Rate Constant for Y-Chromosome SNPs based on Full Sequencing Data.”
Brown, Richard P., and Ziheng Yang. “Rate variation and estimation of divergence times using strict and relaxed clocks.” BMC Evolutionary Biology 11.1 (2011): 271.