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Markets/Return · metric Gold

Tail Mean Difference (TMD)

Capture non-linear return dynamics by measuring the difference between tail means to identify assets with asymmetric return distributions that linear factors miss.

Refresh
daily
History
9.8 yrs
Plan
Gold
56.8/ 100
Stable

S&P 500 (SPY)

2016-09-21 9.8 yrs · 2,454 pts 2026-06-26

Top drivers

tmd_rawupper_tail_meanlower_tail_mean_abs
⌁ mcp.call("adw-106") vADW-106-live-1.0
Use cases

What it unlocks

For an agent

A factor-rotation agent reads ADW-106 each day; when the TMD score rises above 55 (50 = symmetric; current is 56.8, 77th percentile of a 2,454-day history with trend rising) and upper_tail_mean exceeds |lower_tail_mean|, it tilts the factor allocation toward momentum and growth names that benefit from positive skew and de-weights low-volatility defensive factors, embedding the IOM's tmd_raw and methodology_version in the rebalancing log for attribution analysis. A score dropping back below 48 — signaling downside skew — triggers the reverse tilt automatically.

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For the business

A quantitative portfolio manager uses ADW-106's upper_tail_mean and lower_tail_mean fields to inform options-skew trading: when TMD is above 55, right-tail upside is fatter than the left tail, making put spreads relatively cheap and call spreads relatively expensive on a distribution-adjusted basis, which the PM uses to justify a skew-selling strategy. Unlike standard skewness statistics pulled from raw returns, TMD's 60-day normalized output arrives pre-packaged in the IOM structure with source lineage and confidence, saving the quant team the step of cleaning and aligning OHLCV data before running their own tail-mean computation.

Forward outlook

Prediction

Horizon
Recommended use
Capture asymmetric return skew. Score > 55 = upside-dominant tail; < 45 = downside-dominant — adjust directional bias accordingly.
Methodology

How it's built

60-day returns → μ_up (90th pct tail) − |μ_low| (10th pct tail) → normalize by |mean| → map to 0-100 (50=symmetric, >50=upside skew)

Stooq daily OHLCV (SPY, keyless)

Version ADW-106-live-1.0 · validated to beat a naive baseline · benchmark: none