prune {delt} | R Documentation |

## Prepares for pruning an overfitting evaluation tree

### Description

Finds a sequence of nodes of an overfitting evaluation tree
which are candidates to be the pruning nodes.
Pruning a tree means removing a branch starting from a node.

### Usage

prune(et)

### Arguments

`et` |
an evaluation tree;
output of "eval.cart", "densplit", ... |

### Value

A list containing the following components.

`tree` |
the original tree which was given as the input |

`delnodes ` |
vector giving a sequence of nodes in the order in
which we should prune the branches starting from these nodes |

`delend` |
vector whose length is the number of subtrees of the
original tree. With the help of "delend" we define the subtrees.
Elements of "delend" define a sequence of nodes from "delnodes" in the
following way: (1:delend[1]) is the first sequence,
(delend[1]+1:delend[2]) is the second sequence, and so on.
Then, i:th subtree is the result of pruning branches away whose
roots are the nodes which are the first delend[i] elements of delnodes. |

`leafs` |
vector whose length is the number of subtrees of the
original tree; number of leafs of the subtrees |

`alfa` |
vector whose length is the number of subtrees of the
original tree; value of the corresponding alfa (complexity parameter)
for every subtree |

`loglik` |
vector whose length is the number of subtrees of the
original tree; the value of the likelihood criterion for the subtree |

### Author(s)

Jussi Klemela

### See Also

`densplit`

,
`eval.pick`

### Examples

dendat<-sim.data(n=200,seed=5,type="mulmodII")
et<-densplit(dendat)
treeseq<-prune(et)
treeseq$leafs
len<-length(treeseq$leafs)
leaf<-treeseq$leafs[len-10]
leaf
etsub<-eval.pick(treeseq,leaf=leaf)
dp<-draw.pcf(etsub)
persp(dp$x,dp$y,dp$z,phi=25,theta=-120)

[Package

*delt* version 0.8.0

Index]