Figure 3.
Stick-breaking schematic. The stick-breaking property of the Dirichlet process (DP) is used to estimate the number of mutation clusters in the data. For each mutation, a stick of arbitrary length is broken into randomly sized bits that represent a cluster. At point A, breaks have been introduced, corresponding to clusters c1-c4. B shows the stick after introducing break 5, whereas C shows the completed stick-breaking procedure. The size of each broken part represents the weight associated with a cluster and influences the mutation assignments, in which a high weight makes it more likely that a mutation is assigned to that cluster. These weights are updated after probabilities for each cluster have been obtained for each mutation, eventually converging on a solution.