Minimum Data Requirements - Times-to-Failure Data

For reliability growth data analysis only.

The minimum data requirements for analysis of developmental times-to-failure data are presented next:

Data Type

Minimum Requirements

Models

Failure Times

At least 3 unique failures.

Crow-AMSAA, Duane

Crow Extended:
BD modes - at least 3 unique
BD modes - at least 3 unique

Grouped Failure Times

At least 3 unique failures.

Crow-AMSAA, Duane

Crow Extended:
BD modes - at least 3 unique
BD modes - at least 3 unique

Multiple Systems - Known Operating Times

At least 3 unique failures for overall analysis.

Crow-AMSAA, Duane

Crow Extended:
BD modes - at least 3 unique
BD modes - at least 3 unique

Multiple Systems - Concurrent Operating Times

At least 3 total failures for overall analysis.

Crow-AMSAA, Duane

At least 3 unique failures on an individual system to return individual system results.

Crow Extended:
BD modes - at least 3 unique
BD modes - at least 3 unique

Multiple Systems with Dates

At least 3 total failures for overall analysis.

Crow-AMSAA, Duane

At least 3 unique failures on an individual system to return individual system results.

Crow Extended:
BD modes - at least 3 unique
BD modes - at least 3 unique

Multiple Systems with Event Codes

At least 3 total failures for overall analysis.

At least 3 unique failures on an individual system to return individual system results.

Crow Extended:
BD modes - at least 3 unique
BC modes - at least 3 unique
I events apply only to BC modes and there must be an I event for each BC mode