TABLE 1.

Effect of number of markers (M) under the FPD on the confidence interval (C.I.) of QTL location, comparisonwise error rate (P-value), and statistical power, according to the test for significance and standardized allele substitution effect at the QTL (d/σ), using simulated data

		C.I.		P-value					Power
d/σ	M	Δ	SD	Σ(λf)2	max|λ|	max-χ2			Σ(λf)2 (%)	max-χ2 (%)
0.2	25	4.1	3.1	0.003	0.053	0.007	0.015	0.074	99	56
	13	5.1	3.3	0.002	0.030	0.008	0.018	0.076	99	59
	7	6.4	3.6	0.004	0.049	0.006	0.016	0.061	98	64
0.15	25	4.9	5.2	0.008	0.104	0.056	0.067	0.250	92	27
	13	6.3	5.2	0.021	0.071	0.126	0.112	0.260	90	24
	7	7.8	5.9	0.021	0.098	0.130	0.101	0.299	89	28

Tests of significance: Σ(λ_f)², max|λ|, max-χ², , and See text for details. Power was calculated at P-value = 5%. Values Δ and SD characterize the center and size of the confidence interval obtained in jackknife iterations (see text). Parameters of the simulations: chromosome length 120 cM. A single QTL was situated in position 40 cM. Number of families, F = 10 (5 families, sire heterozygous at the QTL; 5 families, sire homozygous at the QTL); number of daughters per family, N = 2000; proportion of the population selected to each tail, 0.10; number of subpools per tail, S = 4. Values are the mean based on 10 simulation data sets; for every data set, 500 permutations and 100 jackknife iterations were made.