The Cost Efficiency of the Brazilian Electricity Distribution Utilities: A Comparison of Bayesian SFA and DEA Models

Table 5

Estimated BSFA (Credible interval in parentheses).

Parameter	M2	M4
${\beta }_0$	$-\mathrm{1,869}$ ($-\mathrm{2,569}$; 1,162)	$-2$,050 ($-2$,691; 1,394)
${\beta }_1$	0,079 (0,002; 0,256)	0,085 (0,002; 0,265)
${\beta }_2$	0,202 (0,087; 0,314)	0,203 (0,101; 0,304)
${\beta }_3$	0,582 (0,548; 0,616)	0,592 (0,561; 0,623)
$\lambda$	4,514 (2,478; 8,790)	—
${\sigma }^2$	16,29 (7,62; 33,15)	16,72 (8,525; 28,450)
${\varphi }_1$	—	0,282 (0,129; 0,449)
${\varphi }_2$	—	0,143 (0,003; 0,5178)