A Successful Three-Phase Metaheuristic for the Shift Minimization Personal Task Scheduling Problem

Table 1

The characteristics of the 14 KEB instances.

KEB#	Opt	#Emps	#Tasks	@AVG	Tightness level	Task skill level	Shift skill level	Overlap level	%ICH	@PAIRS
9	40	49	104	2.6	89.9	35.0	6.52	57.3	98.1	4.15
11	20	24	119	6.0	90.0	36.2	0.24	26.0	96.6	0.90
45	60	67	420	7.0	90.0	33.9	0.05	24.1	97.9	0.92
59	59	70	525	8.9	91.4	34.4	0.01	19.4	96.8	0.83
75	60	72	665	11.1	90.0	34.2	0.001	15.4	98.2	0.88
77	160	180	688	4.3	90.0	33.4	0.87	36.8	99.0	2.77
79	80	94	689	8.6	90.1	33.6	0.01	19.8	99.4	0.99
80	99	112	691	7.0	90.9	33.8	0.05	24.4	99.4	1.03
89	70	88	788	11.3	90.1	34.0	0.001	15.3	98.6	0.86
94	80	93	881	11.0	90.0	33.8	0.001	15.6	98.9	0.89
98	80	91	896	11.2	90.0	34.2	0.001	15.3	99.2	0.94
106	100	121	1096	11.0	90.0	33.3	0.001	15.6	99.7	0.96
107	100	114	1112	11.1	90.0	33.7	0.001	15.4	99.8	0.96
108	128	162	1115	8.7	91.4	33.6	0.008	19.9	99.5	1.00

Three bold values on a row indicate a hard instance.