K=3 backward kernel that closes the forward → loss → backward chain for the trade-outcome aux head. Mirrors `aux_next_bar_backward` (K=2 sibling) line-for-line because gradient flow is K-independent: `d_logits = (softmax − one_hot)/B_valid` propagated through `Linear → ELU → Linear` chain via standard softmax-CE derivative. Per-sample partials (caller reduces via existing K-generic `aux_param_ grad_reduce` kernel): dW1_partial [B, H=128, SH2=256], db1_partial [B, H] dW2_partial [B, K=3, H], db2_partial [B, K=3] dh_s2_aux_out [B, SH2] Mask handling: labels[b] == -1 zeros the K-vector → all downstream partials zero (chain rule's multiplicative zero). All-skip batch produces valid_count=0 → d_logits=0 for every row → zero gradients across the board, no NaN. Sparse-label gradient amplification: B_valid is typically ~1-5% of nominal batch (trade-close events are rare), so inv_B = 1/B_valid is much larger than the K=2 sibling's inv_B = 1/(~B). Per-trade-close gradients have proportionally higher magnitude — correct credit assignment (rare signal speaks louder) but Phase E's Adam may need class-weighted CE or per-group LR tuning. ELU backward via post-activation identity: f'(x) = (h_post > 0) ? 1 : 1 + h_post — recovers derivative without re-evaluating x_pre. SP14 Phase C.5b separation preserved: reads h_s2_aux (aux trunk output), writes dh_s2_aux_out SAXPYing into dh_s2_aux_accum. Q's encoder structurally protected (aux_trunk_backward has no dx_in output). Phase A5 (this commit) is dead code — no Rust launcher. Phase B will land the full launcher chain (gpu_aux_heads.rs parallel ops struct, collector struct fields for W1/W2/b1/b2/Adam-state/saved-tensors/dW- partials, wireup in collect_experiences_gpu). Cubin: aux_trade_outcome_backward_kernel.cubin (24.8 KB). ═══ Phase A complete ═══ A1: ISV slots (none needed — reuses padding 121-123) A2: trade_outcome_label_kernel.cu (label producer)26ce7ba69A3: aux_trade_outcome_forward + save-for-backward wireup07728f9efA4: aux_trade_outcome_loss_reduce_kernel.cu (sparse CE)3ddcfb886A5: aux_trade_outcome_backward_kernel.cu (this commit) All 5 GPU kernels compile, cubins built, build.rs registered. Contract chain composes end-to-end on the GPU side. Phase B (Rust launcher chain + 262-dim input concat) is next. Audit: docs/dqn-wire-up-audit.md Phase A5 section + Phase A summary. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
ml
10-model ML ensemble for the Foxhunt HFT system, built on Candle v0.9.1.
Models
- DQN (Rainbow) — deep Q-network with prioritized replay, dueling heads, noisy nets
- PPO — proximal policy optimization with GAE, LSTM policies, clip-higher
- TFT — temporal fusion transformer for multi-horizon forecasting
- Mamba2 — state space model for sequence prediction
- Liquid Networks — biologically inspired networks for non-stationary data
- TLOB — transformer-based limit order book analysis
- KAN — Kolmogorov-Arnold networks
- xLSTM — extended LSTM architecture
- TGGN — temporal graph neural network
- Diffusion — diffusion-based generative model
Key Modules
ensemble— model ensemble coordination and confidence aggregationhyperopt— PSO-based hyperparameter optimization with per-model adapterstrainers— unified training loops (DQN, PPO, supervised)inference—InferenceAdaptertrait for predictioncheckpoint— model checkpointing and restorationevaluation— walk-forward evaluation pipeline
Usage
use ml::dqn::DQN;
use ml::ppo::PpoTrainer;