Ethereum: what Polymarket prices imply, against what happened
What we measured
What then happened — on the 5-minute and 15-minute windows kept, the variance the mid-window price implied for the remaining half-window was 0.95 × the variance that then happened (95% CI 0.92–0.99) and 0.90 × the variance that then happened (95% CI 0.80–1.01) — with 1 inside the interval on 1 of 2. This comparison does not depend on the law used to invert the price.
Across 3 Ethereum markets, the mid-window implied volatility (normal inversion) is 0.80 × realized on the 5-minute market (95% CI 0.80–0.81, n = 10,533), 0.81 × realized on the 15-minute market (95% CI 0.81–0.82, n = 3,945) and 0.85 × realized on the hourly market (95% CI 0.83–0.86, n = 1,101). The three durations sit within 0.04 of each other.
Through the Student-t (ν = 4) inversion the same Ethereum prices read 1.04 × (5-minute), 1.05 × (15-minute) and 1.10 × (hourly) — at or above realized.
In levels: implied 30.0% (5-minute), 30.6% (15-minute) and 32.5% (hourly) against trailing realized 36.7%, 37.2% and 37.5%, annualized 24/7.
Stability: ratio on the first and second halves of the period — 0.81 / 0.80 (5-minute), 0.82 / 0.81 (15-minute) and 0.84 / 0.85 (hourly).
Highest and lowest nightly ratios — 5-minute: 0.92 on Oct 27, 2026 (n = 136), 0.72 on Oct 11, 2026 (n = 145), 15-minute: 0.98 on Sep 30, 2026 (n = 52), 0.72 on Sep 17, 2026 (n = 48) and hourly: 0.93 on week 2026-W40 (n = 99), 0.79 on week 2026-W38 (n = 109).
Share of windows with Ethereum price and spot on opposite sides of the price to beat (excluded as "side"): 0.5% (5-minute), 0.2% (15-minute) and 0.4% (hourly); above 50% in 24% of 5-minute windows, 21% of 15-minute windows and 23% of hourly windows the implied σ exceeded the trailing realized σ.
Variance ratio on the two halves — 0.97 / 0.94 (5-minute) and 0.83 / 1.02 (15-minute); realized-vs-realized check (resolution series against 1-minute candles) 0.98 and 0.98.
Windows kept by the price band: 49% of 21,428 (5-minute), 55% of 7,134 (15-minute) and 61% of 1,799 (hourly); the rest sat too close to 50¢ or too close to 0 or 1 for a stable inversion.
| market | kept | normal [95% CI] | Student-t | first half | second half | variance ratio, what followed |
|---|---|---|---|---|---|---|
| 5-minute | 10,533 | 0.80 [0.80; 0.81] | 1.04 | 0.81 (n 5,203) | 0.80 (n 5,330) | 0.95 [0.92; 0.99] |
| 15-minute | 3,945 | 0.81 [0.81; 0.82] | 1.05 | 0.82 (n 1,910) | 0.81 (n 2,035) | 0.90 [0.80; 1.01] |
| hourly | 1,101 | 0.85 [0.83; 0.86] | 1.10 | 0.84 (n 522) | 0.85 (n 579) | — |
Over time
By hour of the day
By hour of the day (UTC, window open): the ratio differs between hours on 5-minute, 15-minute and hourly (Kruskal–Wallis p < 0.001). 5-minute: highest at 0:00 (0.92), lowest at 9:00 (0.74), 15-minute: highest at 0:00 (0.95), lowest at 15:00 (0.74) and hourly: highest at 13:00 (1.42), lowest at 16:00 (0.74).
Questions
How many Ethereum windows feed these figures?
10,533 of 21,428 5-minute windows, 3,945 of 7,134 15-minute windows and 1,101 of 1,799 hourly windows — those whose mid-window price sat in the 15%–45% or 55%–85% band, over 75 nights. One minute before the close only 16%, 9% and 7% would remain: that reading is not published.
Are Ethereum levels (implied 30% against realized 37%) published?
Yes for 5-minute, 15-minute and hourly: the two-decimal spot in the collector's logs rounds to 0.29% of a typical half-window move at Ethereum's price (about $2479), under the 1% tolerance set in advance.
At most one short email a week: the track record in three numbers, one research note, one market. You confirm by email; every email has a one-click unsubscribe link.
Paper results · not financial advice · 18+. Data analytics on Polymarket crypto markets.