Time-series analysis examines data ordered over time to identify unusual trends, cycles, or other temporal patterns that row-level checks can miss. section 4.13 section 1.1.1
It complements single-row outlier detection by examining sequences, ordering, frequencies, and gaps. Records may look normal individually while their timing or collective arrangement is unusual. section 4.13
Useful temporal signals include:
- Unusual trends or cycles in financial records. section 1.1.1
- Spikes in purchase records tied to a supplier at the end of each month. section 1.1.1
- Gaps in time with no staff starting, or clusters of staff starting within a few days. section 4.13
