reliability Reliability data sets

Description

A set of data for simple reliablility analyses, taken from the book by Meeker and Escobar.

Usage

data(reliability, package="survival")

Details

• capacitor: Data from a factorial experiment on the life of glass capacitors as a function of voltage and operating temperature. There were 8 capacitors at each combination of temperature and voltage. Testing at each combination was terminated after the fourth failure.

  • temperature: temperature in degrees celcius

  • voltage: applied voltage

  • time: time to failure

  • status: 1=failed, 0=censored

• cracks: Data on the time until the development of cracks in a set of 167 identical turbine parts. The parts were inspected at 8 selected times.

  • day: time of inspection

  • fail: number of fans found to have cracks, at this inspection

• Data set genfan: Time to failure of 70 diesel engine fans.

  • hours: hours of service

  • status: 1=failure, 0=censored

  Data set ifluid: A data frame with two variables describing the time to electrical breakdown of an insulating fluid.

  • time: hours to breakdown

  • voltage: test voltage in kV

• Data set imotor: Breakdown of motor insulation as a function of temperature.

  • temp: temperature of the test

  • time: time to failure or censoring

  • status: 0=censored, 1=failed

• Data set turbine: Each of 432 turbine wheels was inspected once to determine whether a crack had developed in the wheel or not.

  • hours: time of inspection (100s of hours)

  • inspected: number that were inspected

  • failed: number that failed

  Data set valveSeat: Time to replacement of valve seats for 41 diesel engines. More than one seat may be replaced at a particular service, leading to duplicate times in the data set. The final inspection time for each engine will have status=0.

  • id: engine identifier

  • time: time of the inspection, in days

  • status: 1=replacement occured, 0= not

References

Meeker and Escobar, Statistical Methods for Reliability Data, 1998.

Examples

survreg(Surv(time, status) ~ temperature + voltage, capacitor)