# Analyst Revision Momentum (Conceptual — PV Proxies Only)

Analyst consensus upgrades predict future price drift. When a large number of analysts revise
estimates upward, institutions position ahead of the revision — creating volume and price
signatures that are detectable in Price-Volume data before the news is public.

**PV proxies for analyst revision dynamics:**

- **Unusual volume as leading indicator:**
  Institutional accumulation ahead of upgrades produces above-average volume.
  Proxy: `volume / adv20` — sustained elevation over 5–10 days precedes upgrades.
- **Price gap vs. VWAP:**
  Institutional buying pushes the close above the VWAP, creating a positive spread.
  Proxy: `(close - vwap) / (vwap + 1e-6)` — positive values indicate institutional demand.
- **Return median deviation as momentum proxy:**
  Strong upward revision momentum shows up as mean-vs-median divergence.
  Proxy: `ts_mean(returns, 5) - ts_median(returns, 20)` — positive = short-term drift.
- **Momentum persistence after analyst cluster:**
  Stocks that have already drifted up on low volatility tend to continue.
  Proxy: `ts_mean(returns, 21) / (ts_std_dev(returns, 21) + 1e-6)` — Sharpe ratio of returns.

**Expression building blocks (PV only — safe operators):**
```
rank((close - vwap) / (vwap + 1e-6))                       # VWAP deviation rank
rank(ts_mean(volume / adv20, 10))                           # sustained volume elevation
ts_mean(returns, 5) - ts_median(returns, 20)                # mean vs median momentum
rank(ts_mean(returns, 21)) / (rank(ts_std_dev(returns, 21)) + 1e-6)  # normalized drift
signed_power(rank((close - vwap) / (vwap + 1e-6)), 0.5)    # nonlinear VWAP signal
```