strengthi = clamp(rawi × scalei + 50, 0, 100)
房价动量 raw=price_yoy scale=5 weight=0.35 ← Spence costly (成交价不可伪造)
人口净流入 raw=pop_yoy scale=15 weight=0.30 ← Spence "voting with feet"
商业活力 raw=permits_yoy scale=8 weight=0.20 ← 開店成本不可伪造
价格加速度 raw=acceleration scale=5 weight=0.15 ← 趋势二阶导
Pred = Σ (strengthi × weighti),缺信号 → neutral 50 × weight (惩罚不完整)
Δ = Pred − Mom (divergence) — 偏离历史动量越大 = 反推方法论 alpha 越强