# How many levels of the tree should I prune in my decision tree?

9 ビュー (過去 30 日間)
Radoslav Vandzura 2016 年 2 月 20 日

How many levels of the tree should I prune in my decision tree? How can I detect how many levels is appropriate to have?

サインインしてコメントする。

### 回答 (1 件)

MHN 2016 年 2 月 20 日

There is no certain number for that. One way is computing resubstitution error for different pruning level and find the place which adding nodes does not significantly increase your accuracy.
tree = fitctree(X,Y);
er = zeros(max(tree.PruneList),1);
for i = 1:max(tree.PruneList)
ptree = prune(tree,'level',i);
er(i,1) = resubLoss(ptree);
end
plot(max(tree.PruneList):-1:1,er)
for example in the above example, level four is a good choice. There are many methods to find the good pruning (before making the tree or after that), which depends on many factors.

サインインしてコメントする。

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by