Why is PPO so widely used?
mediumAnswer
- PPO is a policy-gradient method with a clipped surrogate objective that prevents the policy from moving too far from the old one at each update.
- It is on-policy, simple to implement, robust across environments with default hyperparameters, and empirically competitive with more complex methods.
- It is the standard algorithm for RLHF of large language models.
Check yourself — multiple choice
- PPO is off-policy and requires huge replay buffers
- PPO uses a clipped surrogate objective to limit policy updates
- PPO does not use a critic
- PPO cannot be used for continuous actions
The clipped surrogate keeps updates conservative — that's the core of PPO.
#policy-methods#actor-critic
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