How many people were on the floor.
Like a thermostat's chart for a house, but for people. Pick a day on the calendar and the chart shows twenty-four hours of the library floor: for every minute the fleet measured, how many people were there, with the range the instrument can honestly give. One paced transmitter, nine receivers, a map calibrated on minutes when the count was known, and a gap wherever nothing was measured. A gap is never a zero.
2026-09-02. Measured to , 611 minutes on 9 receivers. People present for 325 of those minutes. Most at : 3 (2 to 3 or more) people. 58 minutes were beyond the calibrated range. 4 labelled windows on this day.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
|
1
327 min · peak 3+ |
2
611 min · peak 3+ |
3
652 min · peak 3+ |
4
879 min · peak 3 |
5
533 min · peak 3+ |
6
583 min · peak 3 |
|
|
7
645 min · peak 3+ |
8
500 min · peak 3 |
9
712 min · peak 3 |
10
277 min |
11 | 12 | 13 |
| 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| 21 | 22 | 23 | 24 | 25 | 26 | 27 |
| 28 | 29 | 30 |
| Hour | Measured min | Most people | Min with people |
|---|---|---|---|
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| — | — | — | |
| 17 | 3 (2 to 3 or more) | 8 | |
| 55 | 3 (1 to 3 or more) | 28 | |
| — | — | — | |
| — | — | — | |
| 48 | 3 (2 to 3 or more) | 22 | |
| 60 | 3 (1 to 3 or more) | 32 | |
| 60 | 3 (1 to 3 or more) | 33 | |
| 60 | 3 (2 to 3 or more) | 37 | |
| 60 | 3 (2 to 3 or more) | 41 | |
| 60 | 3 (2 to 3 or more) | 36 | |
| 60 | 3 (2 to 3 or more) | 31 | |
| 45 | 3 (2 to 3 or more) | 31 | |
| 26 | 3 (2 to 3 or more) | 8 | |
| 60 | 3 (2 to 3 or more) | 18 |
| Label | From | To | People | Source | Basis |
|---|---|---|---|---|---|
| OL-001 | 2 | diary | Two people filming a promotional video, moving all over the floor, before 11:20 (diary 2026-09-02 §3, the researcher's own timeline). The window edges are the detector's episode edges on nine receivers (§4b); the count is the researcher's. The quiet minutes between this and OL-002 are unlabelled because where the crew stood then is not recorded. | ||
| OL-002 | 2 | diary | Same two people filming (diary 2026-09-02 §3, 'the 10:45 and 10:57 episodes fall in the window the researcher places two people making a video on the floor'). Window edges from §4b; count from the researcher. | ||
| OL-003 | 3 | diary | Three people: the diary's calibration (§10) labels 'eighteen minutes with three people' across the 11:16 to 11:25 and 11:31 to 11:38 episodes, inside the researcher's own 11:20 to 11:45 visit (§3). Window edges from §4b; count from the researcher. | ||
| OL-004 | 3 | diary | Three people, the second of the two episodes the diary's calibration (§10) labels as three people, inside the researcher's 11:20 to 11:45 visit (§3). Window edges from §4b; count from the researcher. |
The instrument behind the count · This day as JSON · The calendar as JSON
How to read it
The count
Each receiver divides its two antenna chains frame by frame. The spread of that ratio over a minute is flat when the room is still and wider when something moves; the fleet level is how many times that spread doubled against each receiver's own empty floor, median over receivers. The count is that level read through a map that passes through the labelled states below. Between two labelled states the map interpolates and says so with its interval.
The interval
The receivers are resampled and the level recomputed; the band that gives is mapped through the same inverse, then widened to every labelled state whose own spread it touches. Two states that the instrument cannot tell apart share one interval. Above the highest labelled state the top of the interval is open: "3 or more" means the instrument stops counting there.
What the map rests on
| People | Minutes | Level (oct) | Spread p10 to p90 |
|---|---|---|---|
| 0 | — | 0.00 | by definition |
| 2 | 8 | 0.88 | 0.50 to 1.18 |
| 3 | 18 | 0.93 | 0.48 to 1.21 |
One integer per minute with an interval, from a piecewise-linear map through the anchors. Zero is the floor by construction. Above the top anchor the upper bound is open.
Gaps and privacy
A minute nobody measured is a gap on the chart and a dash in the table, never a zero. The page publishes a count for a public library floor and the calibration behind it: no position, no device, no address, and the whole page goes dark while a study is running.