SPY vs DIA — Signal Comparison

EdgeOS (Edge Operating System) scans ~3,000 liquid US equities on the daily timeframe using the SCTR score (Stock Chart Technical Rank, 0–100) as the primary momentum filter. A T1 ignition fires when: (1) the bull counter crosses from 0 to 1, (2) SCTR is above 9, and (3) price closes above the Saty ATR +0.236 trigger level. This combination produced a 55% win rate in bull regimes across 799,000 signals over 7 years.

When comparing two stocks, SCTR matters for ranking — not as a hard entry gate. The 7-year backtest showed that lower SCTR stocks in confirmed bull trends outperform high-SCTR stocks (18.7% vs 14.7% progression rate to the +1 ATR target). SCTR measures accumulated momentum, while the signal itself measures the timing of the momentum shift.

The extension score is critical for comparing two active signals: a Tight (0–0.4) extension means the stock is near its Saty ATR baseline with room to run, while an Extended (>1.2) score indicates the stock has moved far from equilibrium and carries higher risk. When both SPY and DIA have active signals, prefer the one with a lower extension score.