Spearman
A rank-correlation statistic applied to price and time, used to gauge how consistently a trend has been moving in one direction — a trend-strength measure borrowed from statistics.
What the numbers mean
The lookback sets how many bars are ranked when correlating price against time. The output runs from +1 (price rose in perfect rank order over the window) through 0 to −1 (fell in perfect order).
- 10 or 20 — the number of bars ranked
- +1 — price rose in perfect rank order across the window
- −1 — fell in perfect order
- 0 — no consistent ordering; chop
How it is used
Read as a measure of how orderly a trend is rather than how large: readings near +1 describe a steady, uninterrupted advance, while readings near zero describe chop regardless of where price ended up.
- Readings near +1 → a steady, uninterrupted advance
- Readings near 0 → chop, regardless of where price ended up
- Used to rank which markets are trending most cleanly right now
How it relates to everything else
Spearman measures the orderliness of a trend where ADX measures its force, and the two can disagree instructively: a violent, gappy advance scores high on ADX and poorly here, while a slow steady grind does the opposite.
- Orderliness, where ADX measures strength
- Ignores the size of moves entirely — only their order
- Useful for screening trend quality across a watchlist
What to watch for
Rank correlation ignores the size of moves entirely — a long grind upward and a violent spike can score identically.