Function gathering several hierarchical ensemble algorithms
Usage
TPR.DAG(S, g, root = "00", positive = "children",
bottomup = "threshold.free", t = 0, w = 0)
Arguments
S
a named flat scores matrix with examples on rows and classes on columns
g
a graph of class graphNEL. It represents the hierarchy of the classes
root
name of the class that it is on the top-level of the hierarchy (def. root="00")
positive
choice of the positive nodes to be considered in the bottom-up strategy. Can be one of the following values:
children (def.): for each node are considered its positive children;
descendants: for each node are considered its positive descendants;
bottomup
strategy to enhance the flat predictions by propagating the positive predictions from leaves to root.
It can be one of the following values:
threshold.free (def.): positive nodes are selected on the basis of the threshold.free strategy (def.);
threshold: positive nodes are selected on the basis of the threshold strategy;
weighted.threshold.free: positive nodes are selected on the basis of the weighted.threshold.free strategy;
weighted.threshold: positive nodes are selected on the basis of the weighted.threshold strategy;
tau: positive nodes are selected on the basis of the tau strategy.
NOTE: tau is only a DESCENS variants. If you use tau strategy you must set the parameter positive=descendants;
t
threshold for the choice of positive nodes (def. t=0.5). Set t only for the variants that requiring
a threshold for the selection of the positive nodes, otherwise set t to zero
w
weight to balance between the contribution of the node \(i\) and that of its positive nodes. Set w only for the
weighted variants, otherwise set w to zero
Value
a named matrix with the scores of the classes corrected according to the chosen algorithm