MDB – Minimal Detectable Bias

The smallest magnitude of a bias in an observation or observation group that can be reliably detected by an overall model test within a specified hypothesis-testing framework.

MDB is derived from reliability theory in least-squares estimation and depends on the observation model, the stochastic model, and the chosen significance and power levels of the statistical test. It provides a quantitative measure of the sensitivity of a geodetic system to undetected systematic errors and is widely used in quality control and reliability analysis of geodetic networks and GNSS observation models.