Tag: deepseek
All the articles with the tag "deepseek".
GRPO and Reinforcement Learning from Verifiable Rewards
Updated:When an answer can be checked, the reward model goes away, and sampling a group of answers per question and comparing them within the group gives the advantage without a value network. Verifiable rewards, GRPO's group-relative advantage worked on four samples, its objective and KL estimator, the memory it saves, why groups that all agree teach nothing, and the length bias Dr. GRPO identified, measured on a toy where length never affects the reward.
Anatomy of a Frontier Model: Reading DeepSeek-V4 Through Part V
Updated:DeepSeek-V4 (April 2026) is two mixture-of-experts models with a million-token context: 1.6 trillion parameters with 49 billion active, and 284 billion with 13 billion active. Read through Part V, each unfamiliar part answers a cost the earlier posts measured: compressed and sparse attention for the KV cache, an indexer for the sparse selection, a widened residual stream kept stable by a doubly stochastic constraint, the Muon optimizer, FP4 experts, and on-policy distillation from more than ten teachers. The KV cache recomputed from the configuration: 2% of a standard model's at a million tokens.