Table 2.

Tests for significance for phase one and phase two positions

Data set	No. of positions	Excess in module boundaries, %	P
Overall intron density
Phase 1
d = 2	94	8.1	0.18
d = 4	350	−6.2	0.53
d = 6	611	−6.8	0.59
d = 8	991	−9.0	0.82
All phase 1	1,740	−5.5
Phase 2
d = 2	38	10.8	0.30
d = 4	206	18.1	0.025
d = 6	610	9.3	0.11
d = 8	1,132	7.8	0.10
All phase 2	1,544	2.1
No. of homologs
Phase 1
h = 1	94	0.3	0.4
h = 5	350	−9.1	0.64
h = 10	611	−11.3	0.86
h = 20	991	−6.9	0.65
All phase 1	1,740	−5.5
Phase 2
h = 1	38	31.7	0.17
h = 5	206	0.9	0.54
h = 10	610	1.0	0.58
h = 20	1,132	2.1	0.50
All phase 2	1,544	2.1

P values are based on 10,000 random samples of a given size. P values in italics are significant at the P = 0.05 level.