手法を比較

	半教師あり決定木	ラベル伝播
分野	機械学習	機械学習
系統	Machine learning	Machine learning
提唱年	2000s	2002
提唱者	Various (Levin & Shapiro; Zhu & Goldberg lineage)	Zhu, X. & Ghahramani, Z.
種類	Semi-supervised classifier / regressor	Graph-based semi-supervised classification
原典	Levin, E. & Shapiro, E. (2000). Learning Decision Trees from Semi-labeled Examples. Proceedings of the ICML Workshop on Attribute-Value and Relational Learning.	Zhu, X., & Ghahramani, Z. (2002). Learning from labeled and unlabeled data with label propagation. Technical Report CMU-CALD-02-107, Carnegie Mellon University.
別名	SSDT, semi-supervised tree induction, self-training decision tree, label-propagation tree	LP, label spreading, graph-based semi-supervised learning, harmonic label propagation
関連	4	3
概要	A Semi-supervised Decision Tree extends standard decision tree induction — such as CART or C4.5 — to exploit unlabeled observations alongside the labeled training set. By iteratively assigning tentative labels to unlabeled data and incorporating them into the growing or splitting process, the algorithm can achieve better accuracy than a fully supervised tree trained on the labeled subset alone, which is especially valuable when labeling is expensive or time-consuming.	Label Propagation is a graph-based semi-supervised learning algorithm introduced by Zhu and Ghahramani in 2002 that spreads class labels from a small set of labeled nodes to a large set of unlabeled nodes by iteratively diffusing label information along the edges of a similarity graph, exploiting the manifold structure of the data.