Neutral, Independent, Finite Sites Models
Most substitution models used to date are neutral, independent, finite sites models.
- Neutral
- Selection does not operate on the substitutions, and so they are unconstrained.
- Independent
- Changes in one site do not affect the probability of changes in another site.
- Finite Sites
- There are finitely many sites, and so over evolution, a single site can be changed multiple times. This means that, for example, if a character has value 0 at time 0 and at time t, it could be that no changes occurred, or that it changed to a 1 and back to a 0, or that it changed to a 1 and back to a 0 and then to a 1 and then back to a 0, and so on.
Read more about this topic: Substitution Model
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