How does Random Forest reduce variance compared to a single decision tree?

How does Random Forest reduce variance compared to a single decision tree?medium

Type: conceptual
Topic: does-random-forest-reduce-variance-compared-to-a-single-de
Frequency: common
Tags: machine-learning, how, does, random, forest, reduce

Answer

By training many deep trees on random bootstrap samples (bagging) and using a random feature subset at each split.

Explanation

By training many deep trees on random bootstrap samples (bagging) and using a random feature subset at each split. Averaging uncorrelated trees cancels out individual noise. The key is decorrelation — if all trees see the same features, they make correlated errors and averaging doesn't help much.

Follow-upCan you give a production example?