Feature statistics turn model inputs into monitoring signals. They help distinguish service failures from data-quality problems and reveal features behaving abnormally even within expected ranges. section 14.3.6
Useful checks include:
- Track means, minimums, maximums, standard deviations, correlations, percentiles, and statistical tests. section 14.3.6
- Compare values with sanity constraints, such as age below 100 or sensor readings between 10 and 12. section 14.3.6
- Add monitoring-only features for unstructured inputs, such as image brightness, text length, or audio frequency distributions. section 14.3.6
A sensor pipeline
A sensor feature may remain inside its permitted range while its mean, percentile distribution, or correlation with another feature shifts sharply. Tracking several statistics can expose this less obvious failure. section 14.3.6
