wwcsz analysis identified atom-resolution starvation + asymmetric
RATIO mismatch as the empirical ceiling on win rate (38.56% vs
break-even 45.3%). Three coupled fixes shipped in one pass per
"no deferrals":
(a) Adaptive RATIO from observed |loss|/|win| EMAs:
- apply_reward_scale tracks max(-scaled, 0) per step (slot 489)
- rl_reward_clamp_controller maintains neg_max_ema (slot 490,
sparse-aware like pos_max_ema)
- RATIO = clamp(MIN=1.0, neg_ema/pos_ema, MAX=3.0); writes to
slot 481
- Removes built-in 3:1 loss-aversion bias when reality is
symmetric (wwcsz: actual avg|loss|/avg(win) = 0.83). Floor
1.0 prevents inverted asymmetry; ceiling 3.0 preserves
original loss-aversion as the worst case.
(b) C51 V_MAX/V_MIN: ratchet → slow EWMA (α=0.001, half-life ~700
steps):
- Static ratchet wasted atom resolution on rare tails — wwcsz
had V_MIN=-60, V_MAX=20 but realized rewards mostly in [-5, +5]
(Δz=4 vs typical reward magnitude 1-5)
- Slow EWMA lets atom span shrink toward active reward range,
gaining resolution where data lives. Floors at [-1, +1]
preserve original C51 baseline as the worst case.
- Slow α gives Q's atom mapping time to be valid across
encoder/head co-adaptation (vs aggressive EWMA which would
invalidate Q's learned distribution every step)
(c) Q→π distillation λ bumped 0.01 → 0.05:
- wwcsz showed KL dropped 2.10 → 0.30 with λ=0.01 — Q signal
landing but conservatively. Bump tests whether stronger Q
pull translates to better policy → better R/done.
Diag exposes neg_scaled_max + neg_scaled_max_ema so the RATIO
adaptation chain is observable.
apply_reward_scale shared_mem doubled from 2× to 3× block × f32
to fit the three parallel reductions (abs, pos, neg).
Companion to investigation (e) — n_rollout_steps controller was
suspected of misalignment (256-8192 vs trade_duration ≈ 6 steps)
but turned out to be a K-loop param, not used in Bellman target.
1-step Bellman with γ-bootstrap is the actual mechanism; closed
without code change.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>