These premade spreadsheets can be used to gain insight into MRCA calculations because they allow you
to experiment with the various parameters.  Sheets are provided for calculations based on the binomial
expansion and the Poisson distribution. The starting point for the calculations is for n = 25 markers and
R = 0.002 per marker per generation.  Iterating the value of G, the sheets show that for k = 0, or no
mismatches, the 50% confidence level is at G = 6.9 generations.
Binomial Expansion MRCA Spreadsheet
Poisson Distribution MRCA Spreadsheet
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