AI by Hand ✍️

AI by Hand ✍️

1. "Expert Choice" Mixture of Experts (MoE)

Frontier AI Drawings by Hand ✍️

Prof. Tom Yeh's avatar
Prof. Tom Yeh
Aug 05, 2025
∙ Paid

The first set of drawings introduces Expert-Choice Mixture of Experts (MoE) and contrasts it with traditional token-choice MoE routing. You’ll see why token-choice routing leads to load imbalance and how Expert-Choice allows each expert to select its top tokens, keeping computation balanced and capacity fully used. This routing strategy was introduced by researchers at Google.

Q: Why Expert Choice routing?

A: Because traditional MoE (Token Choice) suffers from load imbalance—some experts get overloaded with tokens while others stay idle—wasting capacity.

Q: How does Expert Choice fix this?

A: By letting experts select their top tokens, it prevents any expert from being overloaded with tokens and keeps computation balanced.

Q: Who invented Expert Choice routing?

A: Researchers at Google.

This first release takes you into Expert-Choice Mixture of Experts (MoE) and shows you how this method contrasts with traditional MoEs that use token choice.

Q: Why Expert Choice routing?
A: Because traditional MoE (Token Choice) suffers from load imbalance—some experts get overloaded with tokens while others stay idle—wasting capacity.

Q: How does Expert Choice fix this?
A: By letting experts select their top tokens, it prevents any expert from being overloaded with tokens and keeps computation balanced.

Q: Who invented Expert Choice routing?

Researchers at Google.

Drawings

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