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Nilson Rojas

Flyweight · REAL v1.0 (registered) #38; v1.1 (shadow) #36

Descriptive profile. The resume rank is what has been earned; these statistics are context, not a prediction. A test on Oct 20, 2026 found that career statistics add nothing reliable to age, layoff and experience as predictors of the next result (experiments/REGISTER.md, EXP-2026-10-20-14).

Weight band 38-38: the 10th to 90th percentile of his position across weight vectors drawn near the 70/30 weights (the position does not depend on the weights). Rating 1,455, deviation 291: measured from 1 UFC bout; a one-bout newcomer sits near 290. Provisional: 1 UFC bout; the rating rests on little evidence.

Age 27 (born 1999-04-21) · Height unknown · Reach unknown · Stance unknown · 64 days since last bout (2026-08-29) · Last five 0-1 · Streak L1

Why he is ranked here

Rating 1,455 is the division's 42nd highest of 49 board fighters; the ledger stands at -1.0 (less 1.0 for other losses outside the top 5; losses count for three years); 0 quality wins in 15 years, 0 over top-10 opponents; no form penalty (0-1 last five). Score -0.28 = -0.28 (rating term, 70% weight) +0.00 (ledger term, 30% weight) -0.00 (form penalty); score order put him at #38.

Rules, weights and worked examples: methodology.

All 1 UFC bout

Opp. official rank = the UFC media-panel rank of the opponent on the date (C champion, #1 to #15, unranked; n/a before Feb 2013 or where no official board existed). Model p = the predictive model's pre-fight win chance for him (frozen performance-adjusted Elo; bouts before 2020 were in its tuning sample). Linked opponents have a profile.

Career statistics

Through 2026-10-31, UFC bouts only. Percentile = share of the 49 board fighters at Flyweight at or below this value; high is a position in the division, not a verdict.

Board position since Oct 2023

Position on the registered v1.0 board at each weekly snapshot (C = title holder or reserved, drawn at the top; lower is better). Absent from 122 of 132 snapshots (gaps in the line).

Predictive rating by bout

Rating after each UFC bout from the frozen predictive model (performance-adjusted Elo, data/processed/elo_history.csv; a debut starts at 1,500). The resume rating's history is not stored, so this is the predictive line, which is a different number from the resume rating in the header.

Trajectory

No trajectory index: it needs three decided UFC bouts and a bout within the last three years (config/decline.yaml).

Context flags

Descriptive only. Each line is a population fact about fighters like him, not a forecast for him; the register entries hold the measurements.

• Age band: under 30 (age 27). On the board's own history (3,748 bouts between two board fighters, 2014 to 2026) the higher-scored fighter won 64% of bouts when under 30, 59% at 30 to 32, 57% at 33 to 35 and 42 to 46% at 36 and over (EXP-2026-10-20-09). A population rate, not a forecast for him.
• Recent KO/TKO loss: 64 days ago. The Association of Ringside Physicians consensus sets minimum suspensions of 30 days after a head-strike TKO, 60 after a KO and 90 after a KO with loss of consciousness (Neidecker et al. 2019, cited in EXP-2026-10-20-13); UFCStats does not record which applied.
• Provisional: 1 UFC bout; the rating rests on little evidence (deviation 291).
• Not raised: last bout within 12 months.

REAL v1.0 (registered method) · build c166ee8 · data through 2026-10-31 · page built 2026-11-06 · changelog. Independent fan research project built on public UFCStats data. Not affiliated with, sponsored or endorsed by UFC, Zuffa, LLC, TKO Group Holdings, or any athlete. All trademarks belong to their owners and are used only to identify athletes and events.