Table 1 Effect of the selected threshold for minimal twin group size ts₀ on the skeletal map length under low and moderate rates of genotyping errors and 20% of missing data points.

Map			Initial		After cleaning		After saturation		δ
pe	Nm	ts0	Nsk	L	Nsk	L	Nsk	L
0.01	104	4	349	384.2	81	172.1	99	171.8	1.8
		6	128	221.0	65	173.8	77	174.9	2.3
		8	108	237.0	47	175.5	65	174.2	2.7
0.02		3	237	397.8	58	207.3	71	187.9	2.7
		4	102	213.8	38	128.8	47	126.6	2.8
0.01	2 × 104	6	398	472.1	97	216.1	111	217.1	2.0
		8	256	357.9	91	219.9	104	217.4	2.1
		10	178	307.3	71	205.8	83	201.7	2.5
0.02		4	305	406.4	85	208.0	103	200.9	2.0
		5	175	333.6	57	207.6	73	194.3	2.7
		6	110	200.6	42	135.1	56	132.5	2.4
0.01	4 × 104	10	377	461.7	140	244.7	150	253.2	1.7
		12	281	399.4	110	244.7	120	243.5	2.0
		16	195	339.0	95	245.0	108	248.4	2.3
0.02		6	289	446.0	89	262.4	115	249.1	2.2
		8	157	364.9	67	272.9	83	254.4	3.1
		10	94	323.6	50	283.0	67	252.2	3.8

Simulated map length was L = 191.3, 214.6, and 273 cM for populations with N_m = 10⁴, 2 × 10⁴, and 4 × 10⁴ markers, respectively; p_e, level of genotyping errors per marker locus; ts, twin group size, ts₀, threshold ts value: skeletal markers should obey the condition ts ≥ ts₀; N_sk, number of intervals in the map; N_m, number of markers per LG in the initial dataset; δ, map density (the ratio of the entire chromosome map length to the number of intervals).