Every seasonality screener hands you a shortlist. None of them tell you how long the list would
be if the market had no schedule at all. This one does — recomputed every time you move a filter,
from the same null that /evidence is built on.
◷ Loading 23 years across 19 markets…
How the noise number is calculated
The grid
Every weekday × hour bucket in every selected market, pooled across all months and all
years — the same buckets the dashboard reads, on the same UTC bars.
The null
For each bucket we keep its real sample size and ask: if this market had no
hour-of-week structure at all — if every hour simply matched the market's own overall up-rate — how
often would it clear the filter you just set? Summing that probability over every bucket searched
gives the expected number of hits from noise alone.
The baseline
Every figure here — z, the gap, the direction filter — is measured against
that market's own up-rate across all its hours, not against a flat 50%. In FX the two are the
same question: every baseline sits within a point of 50. In the equity indices they are not. NAS100 and
SPX500 close up 52.3% of every hour they trade, so scored against 50 their buckets all look
bullish because the index is. Measured against their own baseline, not one of the four indices
produces a single significant window — which is exactly what
/evidence already concluded by a different route.
Accuracy
Computed analytically (normal approximation to the binomial) so it updates as you type.
It lands a little above the 4,000-draw simulation behind /evidence —
15.3 against 13.6 at our default settings — and we keep the higher number rather than the flattering one.
What it is not
It is not a p-value for any individual row, and a result that beats the noise
count is not thereby a trade. It answers one question: is this shortlist longer than a coin-flip
universe would have handed me?
Read the flags. Windows at the daily rollover (21:00–22:00 UTC) and at the Sunday reopen sit in the
thinnest liquidity of the week, where the spread widens well past the figures used here — the Sunday reopen
is under 4% of all buckets but supplies 6 of our 20 strongest readings, and that is a fact about spreads more
than about edges. The toggles above let you remove both. Historical frequencies are not forecasts and nothing
here is financial advice. See where our own grid fails →