Mine Performance Assessment by Means of Stochastic Frontier Analysis

Table 4

Results of the Tobit regression for mine inefficiency, Stage-2.

Variable	Coefficient	Standard error	t-value (p value)
Panel A: censored Tobit model (dependent variable (inefficiency) = 1-TE)
Constant	-0.0198	0.0240	-0.83 (0.418)
SR	0.0564	0.0081	6.95 (0.000)
Sigma	0.0311	0.0047
Log likelihood = 44.158
Panel B: bootstrapped censored Tobit model (dependent variable (inefficiency) = 1-TE)
Variable	Coefficient	Bootstrapped standard error	t-value (p value)
Constant	-0.0198	0.0236	-0.84 (0.401)
SR	0.0564	0.0090	6.24 (0.000)
Sigma	0.0311	0.0041
Log likelihood = 44.158

Notes: sigma: an estimate of the standard deviation of the error.
The bootstrapped Tobit regression was performed with B (number of replications) = 1000 samples.