Data Analysis of Step-Stress Accelerated Life Test with Random Group Effects under Weibull Distribution

Table 4

Estimates of parameters from Bayesian approaches.

	Parameter	Posterior mean	Posterior variance	Posterior median	Credible interval	MC error
Prior 1	β	0.7652	0.07056^2	0.7588	(0.6356, 0.9077)	0.001916
	β0	39.52	3.657^2	39.87	(34.54, 44.02)	0.1011
	β1	−4.483	0.3292^2	−4.531	(−5.052, −3.91)	0.01258
	σu	1.481	1.261^2	1.148	(0.134, 4.758)	0.0186
Prior 2	β	0.7705	0.0689^2	0.7689	(0.6444, 0.9135)	0.002364
	β0	39.08	2.406^2	39.1	(34.56, 43.9)	0.0933
	β1	−4.423	0.3038^2	−4.423	(−5.035, −3.853)	0.01156
	σu	1.511	1.326^2	1.204	(0.1627, 4.986)	0.0245
Prior 3	β	0.7827	0.05953^2	0.7807	(0.6726, 0.9075)	0.002798
	β0	37.89	1.333^2	38.03	(35.05, 39.88)	0.0987
	β1	−4.28	0.1738^2	−4.297	(−4.563, −3.908)	0.001574
	σu	1.695	1.414^2	1.325	(0.1824, 5.338)	0.0357