This program calculates maximum-likelihood estimate of the TMRCA and its probability using equations (5) and (12) of Walsh 2001. The hyperparameter lambda is set equal to zero. The confidence interval is computed using the algorithm from McGee's Y-Utility and is based on the 2.5% and 97.5% cummulative probabilites.

The purpose of this calculator is to compute an estimated TMRCA and the confidence interval for large numbers of STR reported in NGS tests such as BigY. These tests yield about 400 STR but unfortunately for about 300 of those the mutation rate is unknown. Furthermore the set of markers that can be compared between two persons varies so the mutation rate will vary by comparison in an unknown way; the effect will be small if so long as the markers that are sometimes counted are typical.

The default mutation rate assumed here is that of the FTDNA 111 marker set. The default years per generation and and of testers are the values used by YFULL in their computations.

   Compared STRs                       Differences                       Mutation Rate

   Years Per Generation                Age of Testers

  MLE
Generations Ago  
Years Ago  
Year of Birth  
Probability TMRCA = MLE  


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