... generation.1
An important assumption of the coalescent is that populations are large enough that we can ignore the possibility that there is more than one coalescent event in a single generation. We also only allow coalescence between a pair of alleles, not three or more. In both ways the mathematical model of the process differs from the diagram in Figure 1.
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... is,2
Though you may not remember it.
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... that.3
Remember that we're counting generations backward in time, so when I say that a coalescent event occurred at time $t$ I mean that it occurred $t$ generations ago.
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....4
If you've had a little bit of probability theory, you'll notice that equation 1 shows that the coalescence time is a geometric random variable.
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... alleles.5
Okay, okay. What I should really have said is ``It's not too hard to extend this approach to multiple alleles.''
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... follows6
Using logic just like what we used in the two allele case.
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... is7
If you don't see why, don't worry about it. You can ask if you really care. We only care about $\bar t$ for what follows anyway.
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