Spec: describe only files this dataset contains (drop meta-debug.json, gps.csv)

data/data_dictionary.md

@@ -2,9 +2,9 @@
 
 This document has two parts:
 
-1. **The LEVEL session format** -- what the LEVEL Collector app writes for every recording: the files,
-   their columns, units and clocks.
-2. **This dataset** -- how the recordings are organized here, what was added (run info, a
+1. **The LEVEL session format** -- the files of a LEVEL Collector recording that this dataset
+   contains: their columns, units and clocks.
+2. **This dataset** -- how the recordings are organized here, what was added (the session context, a
    coordinate-free GPS profile, the watch data, the session table), and how they were de-identified.
 
 Conventions used throughout: times are **integer microseconds since the Unix epoch (UTC)** unless stated
@@ -25,8 +25,7 @@ by their time column without any offset.
 |---|---|---|
 | `imu-<placement>-<id>.csv` | always, one per LEVEL sensor | accelerometer + gyroscope samples |
 | `meta-summary.json` | always | app, session timing, sensors, transports, settings, file list |
-| `meta-debug.json` | most sessions (debug builds of the app) | diagnostics: phone battery, phone model, other Bluetooth devices, the sensor time-sync result. **Not published in this dataset**: its values are columns of `context/session_context.csv` (2.2) |
-| `barometer.csv`, `steps.csv`, `gps.csv` | when the phone sensor is enabled | phone streams |
+| `barometer.csv`, `steps.csv` | when the phone sensor is enabled | phone streams |
 | `polar_<id>_{hr,ecg,acc}.csv` | when a Polar H10 is paired | chest-strap add-on streams |
 
 ### 1.2 LEVEL sensor -- `imu-<placement>-<id>.csv`
@@ -45,9 +44,9 @@ numeric order.
 | `time_sensor` | ms | the sensor's own clock, 16-bit (wraps every 65.5 s); absent in the earliest app build |
 | `time_host` | ms | host clock when the packet arrived (bursty; recordings from 2026-09 on) |
 
-The sampling rate is in `meta-summary.json` (`settings`); samples per packet too for `schema_version` 1,
-in `meta-debug.json` (`settings`) from `schema_version` 2 (`lvl_running.Session.settings` merges both; in this
-dataset it is the `samples_per_packet` column of `context/session_context.csv`). Recordings made
+The sampling rate is in `meta-summary.json` (`settings`). Samples per packet is there too for
+`schema_version` 1; for `schema_version` 2 it is the `samples_per_packet` column of
+`context/session_context.csv`. Recordings made
 before LEVEL Collector's 2026-09 rename call `frame_sensor` / `time_sensor` `frame_number` /
 `raw_counter`; this dataset publishes them under the current names.
 
@@ -84,33 +83,14 @@ before LEVEL Collector's 2026-09 rename call `frame_sensor` / `time_sensor` `fra
 | `files[]` | per file: `name`, `modality` (e.g. `ACCEL_GYRO`), `shortMac`, `rotationCount`, `units` |
 | `notes`, `uncleanShutdown` | free text; schema 1's flag for a session the app was closed during (schema 2: `session.endReason`) |
 
-### 1.4 `meta-debug.json` (schema_version 2 to 5)
-
-*Part of the LEVEL format, but not published in this dataset (like the app's other diagnostic files):
-the values a reader needs are columns of `context/session_context.csv` (2.2) and `sessions.csv` (2.5).*
-
-| Key | Meaning |
-|---|---|
-| `phoneBattery.start` / `.end` | `percent`, `voltageMv`, `temperatureC` of the host phone |
-| `settings.samples_per_packet` | samples per radio packet (schema 5, alongside meta-summary schema 2) |
-| `sensorTimeSync.mode` | the time-sync mode used (e.g. `HARDWARE_TS_TB`) |
-| `sensorTimeSync.verdict` | `ALIGNED` or `MISALIGNED`: whether the sensors' clocks agreed |
-| `sensorTimeSync.sensors[]` | per sensor: `shortMac`, `label`, `clockOffsetVsBeaconMs`, `aligned`. `clockOffsetVsBeaconMs` = the median of (`time` − `time_host`) over the sensor's last 200 samples, minus the same for the reference sensor, in ms, taken when the session ends; the reference sensor reads 0, and \|offset\| ≤ 50 ms counts as aligned. It is one end-of-session value, not a maximum |
-| `phone` | host phone: `manufacturer`, `model`, `device`, `androidRelease`, `sdkInt` (app builds from 2026-09-21) |
-| `bluetooth[]` | every *other* Bluetooth device connected during the session (LEVEL sensors excluded): `shortMac`, `deviceClass` (e.g. `AUDIO_VIDEO_HEADPHONES`, `WEARABLE`), `firstSeenMs` / `lastSeenMs` (session-relative), `presentAtStart`, `presentAtEnd`, `connectCount` (app builds from 2026-09-21; device names are removed in this dataset) |
-
-A `MISALIGNED` verdict means timing *between* sensors (e.g. left vs right foot) is unreliable in that
-session; each sensor's own signal is unaffected.
-
-### 1.5 Phone streams
+### 1.4 Phone streams
 
 | File | Columns |
 |---|---|
 | `barometer.csv` | `timestamp` (us), `pressure_hPa`, `altitude_m` (barometric), ~1 Hz |
 | `steps.csv` | `timestamp` (us), `step_count` -- one row per step detected by the phone, counting from 1 |
-| `gps.csv` | `Timestamp` (us), `Latitude`, `Longitude` (deg), `Accuracy_m`, `Speed_mps`, `Bearing_deg`, `Altitude_m`, `Provider` |
 
-### 1.6 Polar H10 chest strap -- `polar_<id>_{hr,ecg,acc}.csv`
+### 1.5 Polar H10 chest strap -- `polar_<id>_{hr,ecg,acc}.csv`
 
 | File | Columns |
 |---|---|
@@ -122,7 +102,7 @@ The strap sends samples in batches, so one `RECEIVED_TIMESTAMP` (the host clock
 with the rest of the session) repeats across a batch. `DEVICE_TIMESTAMP` is the strap's own clock: use
 its differences for sample spacing, and `RECEIVED_TIMESTAMP` to align with the other streams.
 
-### 1.7 Time and units
+### 1.6 Time and units
 
 Every timestamp on the session clock is an integer in **microseconds**, so any two files align
 directly. Clocks that belong to a device keep that device's native unit.
@@ -133,12 +113,11 @@ directly. Clocks that belong to a device keep that device's native unit.
 | `time_sensor` | `imu-*.csv` | the LEVEL sensor's own clock | ms |
 | `time_host` | `imu-*.csv` | the host clock at packet arrival | ms |
 | `timestamp` | `barometer.csv`, `steps.csv` | session clock | us |
-| `Timestamp` | `gps.csv` | session clock | us |
 | `time_us` | `pace_profile.csv` | session clock | us |
 | `RECEIVED_TIMESTAMP` | `polar_*.csv` | session clock, at arrival | us |
 | `DEVICE_TIMESTAMP` | `polar_*_ecg.csv`, `polar_*_acc.csv` | the strap's own clock | ns |
 | `time`, `start_time` | `fit3/*.csv` | session clock | us |
-| keys ending in `Ms` | `meta-*.json` | as named (epoch or session-relative) | ms |
+| keys ending in `Ms` | `meta-summary.json` | as named (epoch or session-relative) | ms |
 
 ---
 
@@ -182,10 +161,10 @@ them, so the folders are anonymous on their own and this file sets the release's
 | `terminated_early` | `true` when the recording did not cover the whole run or event |
 | `unreliable_sensors` | `;`-list of placements whose data should not be used in that session (e.g. a sensor that came loose); `null` when all are usable |
 | `clock` | `synthetic` or `real` (see 2.6) |
-| `gps` | `profile` (coordinate-free `pace_profile.csv` only) or `route` (also the raw `gps.csv`) |
+| `gps` | `profile`: the phone GPS track is released only as the coordinate-free `pace_profile.csv` (2.3) |
 | `time_method` | how `time` was placed on the host clock (1.2.1): `first_sample_anchor` |
-| `time_sync_mode`, `time_sync_verdict` | the sensor time-sync mode and its result, `ALIGNED` / `MISALIGNED` (1.4); `null` when that app build did not record it |
-| `samples_per_packet` | samples per radio packet, where the app recorded it outside `meta-summary.json` |
+| `time_sync_mode`, `time_sync_verdict` | the sensor time-sync mode (e.g. `HARDWARE_TS_TB`) and its result: `ALIGNED` when every sensor's clock agreed with the reference sensor's within 50 ms at the end of the session, else `MISALIGNED`. `MISALIGNED` means timing *between* sensors (e.g. left vs right foot) is unreliable in that session; each sensor's own signal is unaffected. `null` when that app build did not record it |
+| `samples_per_packet` | samples per radio packet, for recordings whose `meta-summary.json` (schema 2) does not carry it |
 | `phone_model` | the recording phone (manufacturer and model) |
 | `bluetooth_devices` | other Bluetooth devices connected to the phone during the session, as recorded by the app: `;`-list of `headphones` / `watch` / `other`, or `none`; `null` for app builds before 2026-09-21 |
 | `phone_battery_start_pct`, `phone_battery_end_pct`, `phone_temp_start_c`, `phone_temp_end_c` | the recording phone's battery level and temperature at the start and end |
@@ -248,7 +227,7 @@ One row per session; columns in groups, read left to right.
 | | `long_gaps_per_hour` | gaps longer than 150 ms (3 or more lost packets) per hour of recording, worst sensor: separates a clean link from a bursty one when `loss_pct` is similar |
 | | `data_ends_early_s` | seconds between the end of the session and the last sample of the sensor that stopped first; ~0-10 s is normal, more means a sensor or the link stopped before the recording did |
 | | `terminated_early` | from `context/session_context.csv` |
-| | `time_sync_verdict` | `ALIGNED` / `MISALIGNED` (1.4), from `context/session_context.csv` |
+| | `time_sync_verdict` | `ALIGNED` / `MISALIGNED`, from `context/session_context.csv` (2.2) |
 | | `unreliable_sensors` | from `context/session_context.csv` |
 | | `phone_battery_start_pct`, `phone_battery_end_pct`, `phone_temp_start_c`, `phone_temp_end_c` | host phone, from `context/session_context.csv` |
 | | `sensor_voltage_start_v`, `sensor_voltage_end_v`, `sensor_temp_start_c`, `sensor_temp_end_c` | LEVEL sensors: lowest voltage and highest temperature across the sensors, from `context/session_context.csv` |
@@ -281,26 +260,27 @@ the context. The analysis reports may name public events in prose.
   here.)
 - **Location.** Every run's GPS route is released only as `pace_profile.csv` (no coordinates,
   heading or place names; distance and elevation relative to the first fix), and `barometer.csv` is
-  relative to its first sample -- no absolute altitude or air pressure. (`context/session_context.csv` `gps` =
-  `profile`; `route`, with the raw `gps.csv`, is allowed by the format but unused here.)
+  relative to its first sample -- no absolute altitude or air pressure.
 - **Devices.** Sensor and strap ids are pseudonyms assigned per participant (`0000`, `1111`, ... in
   order of first use), so the same physical unit carries a different id under each participant and
   shared equipment never links two people. Within a participant an id always means the same unit. The
   host's USB device path is removed.
-- **Time sync.** Only the result is published (mode, verdict, per-sensor offset); how the sensor clocks
-  are synchronized is not.
+- **Time sync.** Only the result is published (mode and verdict); how the sensor clocks are
+  synchronized is not.
 - **Heart.** Every participant with a chest strap has heart rate and RR intervals (HRV is derivable);
   the raw ECG waveform is included only where the participant agreed to its release (S01: yes).
-- **Other Bluetooth devices.** Their advertised names (often personal) are removed; class and timing
-  are kept.
+- **Other Bluetooth devices.** Only their type is published (`headphones`, `watch`, `other`); names
+  (often personal) and addresses are not.
 - **Watch.** Re-written into our schema (2.4): no account ids, other workouts, free text or route.
 - **Named locations.** A run's place is published only where the participant chose to (`location` in
   `context/session_context.csv`); the route itself is still coordinate-free and the clock still synthetic.
 - **Notes.** The only free text released is the session's `notes` (2.2) and the operator's `notes` in
   `meta-summary.json`; neither carries names, initials, place names (a published location is simply
   omitted there) or, on synthetic-clock runs, clock times.
-- **Not released:** calibration recordings, any participant who did not agree to release, `gps.csv` for route-anonymized runs, the watch's route,
-  the Samsung export files, raw ECG for participants who did not opt in, the collection-day notes, and the app's debug log and link telemetry.
+- **Not released:** calibration recordings, any participant who did not agree to release, the raw GPS
+  route (phone and watch), the Samsung export files, raw ECG for participants who did not opt in, the
+  collection-day notes, and the app's diagnostic files (its values that matter are in
+  `context/session_context.csv`).
 
 ### 2.7 `context/participants.csv`