A class for a log prior based on a Catalan number prior. More...
Public Member Functions | |
cxsc::real | operator() (const size_t k) const |
Get log prior value for state with k splits. | |
cxsc::real | changeOnSplitOne (const size_t k) const |
Get the change in log prior value when a state with k splits is split once more. | |
cxsc::real | changeOnMergeOne (const size_t k) const |
Get the change in log prior value when a state with k splits has one cherry merged. |
A class for a log prior based on a Catalan number prior.
The prior is related to the Catalan number of the number of bisections of the root box k, Ck. After k splits there are Ck distinct possible full binary trees and so, for each k, total probability of all the states resulting from k splits is proportional to 1/Ck. If each of these k-split states is equally likely then then the probability of any one k-split state is 1/(Ck^2)