censored data

Censored data occurs when information about a measurement is only partially known. For example, in a study tracking time until an event (like equipment failure), some subjects may not experience the event before the study ends or are lost to follow-up, so their exact time is unknown—only that it exceeds a certain point. This incomplete data is "censored." Recognizing and properly analyzing censored data ensures accurate statistical conclusions, especially in survival analysis or reliability testing, where not all outcomes are fully observed.