Failure data

A statistical study of the relationship between two or more variables. Regression analysis is a process used to define the mathematical relationship or model between two or more variables. When analyzing time-to-failure data, this is commonly called Weibull analysis in which one may or may not attempt to fit a Weibull distribution to the data.

The mathematical and/or graphical analysis of time-to-failure data of items in use by customers. Analysis of field data enables an estimate of the actual field time-to-failure distribution or failure rate.

Statistical analysis of failure data to determine the age-reliability characteristics of an item.

The difference between the failure rate of an item on newly designed equipment and the expected failure rate after product improvement to eliminate dominant failure modes; this reduction in the failure rate is generally exponential and can be predicted from early failure data.