Statistical Analysis of a Weibull Extension with Bathtub-Shaped Failure Rate Function

Table 7

Estimation results using data in Chen [6].

Parameter	MLE	MOM	MMOM	IMOM	MIM
	0.5068	0.5471	0.5071	0.4648	0.4584
	63.8939	102.2165	64.7495	40.3122	41.5428
Approach		95% confidence interval for			Length
Chen’s (Wu’s exact )		(0.1900, 0.6200)			0.4300
Wu’s exact ()		(0.3783, 0.7049)			0.3266
Wu’s approximated ()		(0.3803, 0.6957)			0.3154
MOM pivot		(0.3013, 0.6492)			0.3479
MIM pivot		(0.2955, 0.5998)			0.3043