Files
Chan/ChanMacro/expectancy/decay.py
T
jackyu66gitandClaude 71951019fb chanmacro: Signal Expectancy Engine V1 — Market Memory System
Phase A-C complete: 4 core factors, regime detection, signal tracking, Bayesian expectancy.

chanmacro/ (32 files, ~4000 lines):
- models: 12 enums + 15 Pydantic v2 models (DateAwareModel, MarketStateVector, etc.)
- fetchers: OHLCV + Breadth (from data_provider) + Derivatives (new endpoint)
- scoring: Price Structure / Breadth (quantile buckets) / OI Matrix (5 discrete states) / Volatility Regime
- regime_detector: 3-state (TREND/RANGE/PANIC), factor-locked (Price+Breadth+Vol), versioned, 2-day confirmation
- expectancy: SignalTracker (record+outcomes), TimeDecay (half-life=180d), BayesianExpectancyEngine (Empirical Bayes, Leveled, SufficiencyGuard)
- validation: FactorValidator (IC/ICIR/Hit Ratio), RegimeValidator (MI/KL/ANOVA), TransitionValidator (stability)
- CLI: fetch|score|regime|track|backfill|expectancy|validate|serve
- tests: 52 passing (models, scoring, regime, expectancy)

data_provider:
- /api/derivatives endpoint: funding rate, OI, OI change, basis
- _derivatives storage: same persist pattern as K-line (merge→lock→snapshot→atomic write)
- background refresh every 60s

Co-Authored-By: Claude <noreply@anthropic.com>
2026-06-24 17:44:55 +08:00

56 lines
2.0 KiB
Python

"""
expectancy/decay.py — Time-weighted sample decay.
2024 market structure ≠ 2026 market structure.
Recent samples get higher weight via exponential decay.
"""
from datetime import date as Date
from typing import Optional
import numpy as np
class TimeDecay:
"""Exponential time decay for sample weighting."""
def __init__(self, half_life_days: int = 180):
self.half_life = half_life_days
self._decay_rate = np.log(2) / half_life_days
def weight(self, sample_date: Date, reference_date: Optional[Date] = None) -> float:
"""
Compute decay weight for a sample.
weight = exp(-days_ago * decay_rate)
"""
if reference_date is None:
reference_date = Date.today()
days = (reference_date - sample_date).days
return np.exp(-days * self._decay_rate)
def weights(self, dates: list[Date], reference_date: Optional[Date] = None) -> np.ndarray:
"""Compute decay weights for a list of dates."""
return np.array([self.weight(d, reference_date) for d in dates])
def weighted_win_rate(self, wins: np.ndarray, weights: np.ndarray) -> float:
"""Weighted win rate: sum(wins * weights) / sum(weights)."""
total_weight = weights.sum()
if total_weight == 0:
return 0.0
return float((wins * weights).sum() / total_weight)
def weighted_mean(self, values: np.ndarray, weights: np.ndarray) -> float:
"""Weighted mean."""
total_weight = weights.sum()
if total_weight == 0:
return 0.0
return float((values * weights).sum() / total_weight)
def effective_samples(self, weights: np.ndarray) -> float:
"""Effective number of samples after decay weighting."""
return float(weights.sum())
@staticmethod
def weight_at_age(days_ago: int, half_life_days: int = 180) -> float:
"""Quick weight lookup for a given age in days."""
return np.exp(-days_ago * np.log(2) / half_life_days)