A Scheduling Problem to Minimize Total Weighted Tardiness in the Two-Stage Assembly Flowshop

Table 5

The performance summary of the four heuristic algorithms for large-size problems.

n	m	HEDD		HWT		WSPTMAX		WSPTAVER
		Aver. error	NO	Aver. error	NO	Aver. error	NO	Aver. error	NO
30	2	0.776	50	0.681	51	0.690	48	0.698	31
	4	0.760	51	0.658	74	0.712	35	0.728	20
	6	0.761	53	0.679	74	0.728	27	0.756	26
60	2	0.743	59	0.694	46	0.693	53	0.710	22
	4	0.743	60	0.686	78	0.743	27	0.774	15
	6	0.747	56	0.658	94	0.737	21	0.759	9
90	2	0.740	58	0.696	53	0.703	44	0.718	25
	4	0.731	60	0.671	89	0.739	21	0.760	10
	6	0.734	60	0.675	104	0.753	11	0.782	5
120	2	0.733	60	0.713	51	0.731	49	0.752	20
	4	0.738	59	0.676	98	0.745	15	0.773	8
	6	0.740	58	0.672	111	0.761	8	0.789	3
150	2	0.729	61	0.707	43	0.728	50	0.746	26
	4	0.732	60	0.676	99	0.748	16	0.774	5
	6	0.729	60	0.676	104	0.771	12	0.802	4
180	2	0.746	57	0.705	52	0.716	45	0.735	26
	4	0.731	60	0.676	106	0.761	9	0.788	5
	6	0.724	60	0.659	115	0.765	4	0.796	1
210	2	0.744	59	0.711	49	0.719	55	0.741	17
	4	0.736	60	0.674	105	0.764	10	0.788	5
	6	0.737	59	0.669	115	0.774	6	0.803	0
240	2	0.743	59	0.707	56	0.723	43	0.743	22
	4	0.728	60	0.676	110	0.763	8	0.793	2
	6	0.721	60	0.668	116	0.776	3	0.809	1
270	2	0.730	60	0.697	52	0.711	50	0.730	18
	4	0.726	61	0.673	107	0.756	10	0.782	2
	6	0.727	59	0.658	120	0.765	1	0.802	0