exp_test_demo: Reliability Test Length from Null and Alternative Hypotheses,...

In jjw3952/mcotear: Contains helpful functions for use within MCOTEA

Reliability Test Length from Null and Alternative Hypotheses, alpha, and beta

Description

exp_test_demo calculates the required test length, and allowable number of failures for a reliability demonstration test, given null and alternative hypotheses for MTTF/MTBF, alpha and beta error rates, and assuming the times are exponentially distributed. Hypothesis should be of the form, h0: MTBF <= X; h1: MTBF > X+Y, where X and Y are both positive values. This function comes from the AFIT COEF Reliability Test Planning for Mean Time Between Failures V2 document. Visit https://www.afit.edu/stat/

Usage

exp_test_demo(mtbf0, mtbf1, alpha = 0.2, beta = 0.2)

Arguments

mtbf0	A numeric value indicating the null hypothesis for MTBF/MTTR.
mtbf1	A numeric value indicating the alternative hypothesis for MTBF/MTTR. (hours, miles, rounds, etc.).
alpha	The desired level of significance (type 1 error rate) (values within 0.0:1.00, default is set to 0.20).
beta	The maximum allowable type II error rate (values within 0.0:1.00, default is set to 0.20).

Value

The output is a list supplying required test length (T), allowable number of failures (Accept), the number failures at which you would fail to reject the null hypothesis (i.e. you would reject the system) (Reject), and true type II error rate (Beta) (type II error rate = probability the null hypothesis is not rejected when it is false).

References

FIT COEF Reliability Test Planning for Mean Time Between Failures V2 https://www.afit.edu/stat/

See Also

exp_mtbf_req, exp_reliability_req, exp_test_duration, exp_mean_lcb, exp_rel_power, exp_equal_mtbf, exp_oc

Examples

# What is the required test length and allowable number of failures,  
  # to demonstrate MTBF > 180 with confidence and ensuring there
  # is 80% power we accept a system with MTBF > 300
  # (assuming the times between failure are exponentially distributed)?
mcotear:::exp_test_demo(mtbf0 = 180, mtbf1 = 300, alpha = 0.2, beta = 0.2)

jjw3952/mcotear documentation built on Sept. 2, 2023, 10:30 a.m.