Operational Efficiency Forecasting Model of an Existing Underground Mine Using Grey System Theory and Stochastic Diffusion Processes

Table 14

Summary statistics.

Statistic parameter	Value
	Year
	6	7	8	9	10
Sample	500	500	500	500	500
Mean (expected) value of DOL	1.491	1.525	0.951	1.403	1.574
Median	1.469	1.494	0.945	1.397	1.571
Standard deviation	0.2512	0.2745	0.2631	0.2740	0.3163
Max.	2.470	2.543	1.766	2.471	2.940
Min.	0.9073	0.8394	0.2065	0.5978	0.5828
Range	1.562	1.703	1.559	1.872	2.357
Q (75%)	1.646	1.698	1.105	1.573	1.752
Q (25%)	1.293	1.340	0.761	1.227	1.379
Q (75%)–Q (25%)	0.352	0.358	0.344	0.346	0.373
Asymmetry (Skewness)	0.6235	0.5085	0.4129	0.3726	0.2453
Kurtosis	0.3917	0.3205	0.2378	0.7502	1.1323
Standard error	0.01123	0.01227	0.01176	0.01225	0.01414
Reliability coefficient ()	0.95	0.95	0.95	0.95	0.95
Reliability factor	1.96	1.96	1.96	1.96	1.96
Reliability interval-upper limit	1.513	1.549	0.973	1.427	1.601
Reliability interval-lower limit	1.469	1.501	0.927	1.378	1.545
Mean (expected) value (%)	52.90	53.80	51.40	50.20	50.70