A valid bin is any period of `BIN_SIZE` minutes starting from midnight with at least 1 row from any phone sensor. `PHONE_VALID_SENSED_BINS` are used to compute `PHONE_VALID_SENSED_DAYS`, to resample fused location data and to compute some screen features.
!!! hint
`PHONE_VALID_SENSED_DAYS` are an approximation to the time the phone was sensing data so add as many sensors as you have to `[PHONE_VALID_SENSED_BINS][PHONE_SENSORS]`
Parameters description for `PHONE_VALID_SENSED_BINS`:
| `[PHONE_SENSORS]` | One or more sensor config keys (e.g. `PHONE_MESSAGE`) to be used to flag a bin as valid or not (whether or not a bin contains at least one row from any sensor)|
!!! info "Possible values for `[PHONE_VALID_SENSED_BINS][PHONE_SENSORS]`"
```yaml
PHONE_MESSAGES
PHONE_CALLS
PHONE_LOCATIONS
PHONE_BLUETOOTH
PHONE_ACTIVITY_RECOGNITION
PHONE_BATTERY
PHONE_SCREEN
PHONE_LIGHT
PHONE_ACCELEROMETER
PHONE_APPLICATIONS_FOREGROUND
PHONE_WIFI_VISIBLE
PHONE_WIFI_CONNECTED
PHONE_CONVERSATION
```
## Phone Valid Sensed Days
On any given day, a phone could have sensed data only for a few minutes or for 24 hours. Features should considered more reliable the more hours the phone was logging data, for example, 10 calls logged on a day when only 1 hour of data was recorded is a less reliable feature compared to 10 calls on a day when 23 hours of data were recorded.
Therefore, we define a valid hour as those that contain a minimum number of valid bins (see above). We mark an hour as valid when contains at least `MIN_VALID_BINS_PER_HOUR` (out of 60min/`BIN_SIZE` bins). In turn, we mark a day as valid if it has at least `MIN_VALID_HOURS_PER_DAY`. You can use `PHONE_VALID_SENSED_DAYS` to manually discard days when not enough data was collected after your features are computed.
Parameters description for `PHONE_VALID_SENSED_DAYS`:
