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. Author manuscript; available in PMC: 2010 Aug 16.
Published in final edited form as: Behav Genet. 2009 Jun 14;39(5):580–595. doi: 10.1007/s10519-009-9281-0

Table 2.

Empirical Type 1 error rates for tests of equality of three means with total sample size of N = 400, allele frequency of P = 0.50 (nGG = 100, nGg = 200, ngg = 100), negative (upper-half), and positive (lower-half) pairing of sample sizes and variances

Test Error distribution (GG Gg gg) σ2 per group α = 0.05 α = 0.01 α = 0.001
F-test (Y) Normal 2.0 1.0 2.0 0.07802¥ 0.01982¥ 0.00286¥
F-test (Blom) Normal 0.07189¥ 0.01763¥ 0.00249¥
Welch test (Y) Normal 0.05021 0.00982 0.00093
Welch test (Blom) Normal 0.04709 0.00896 0.00083
F-test (Y) LaPlace 2.0 1.0 2.0 0.07735¥ 0.01970¥ 0.00272¥
F-test (Blom) LaPlace 0.06774¥ 0.01587¥ 0.00196¥
Welch test (Y) LaPlace 0.04897 0.00951 0.00090
Welch test (Blom) LaPlace 0.04918 0.00947 0.00087
F-test (Y) χ(1)2 2.0 1.0 2.0 0.07641¥ 0.01890¥ 0.00251¥
F-test (Blom) χ(1)2 0.97045¥ 0.89414¥ 0.70173¥
Welch test (Y) χ(1)2 0.06122¥ 0.01718¥ 0.00358¥
Welch test (Blom) χ(1)2 0.96537¥ 0.87953¥ 0.66590¥
F-test (Y) Weibull (1, 0.5) 2.0 1.0 2.0 0.07067¥ 0.01461¥ 0.00169¥
F-test (Blom) Weibull (1, 0.5) 0.99981¥ 0.99869¥ 0.98711¥
Welch test (Y) Weibull (1, 0.5) 0.08008¥ 0.02698¥ 0.00684¥
Welch test (Blom) Weibull (1, 0.5) 0.99976¥ 0.99820¥ 0.98406¥
F-test (Y) Normal 1.0 2.0 1.0 0.02975 0.00462 0.00042
F-test (Blom) Normal 0.02721 0.00395 0.00028
Welch test (Y) Normal 0.05043 0.01000 0.00096
Welch test (Blom) Normal 0.04655 0.00881 0.00082
F-test (Y) LaPlace 1.0 2.0 1.0 0.02943 0.00475 0.00030
F-test (Blom) LaPlace 0.03297 0.00524 0.00038
Welch test (Y) LaPlace 0.04889 0.00969 0.00086
Welch test (Blom) LaPlace 0.04815 0.00936 0.00084
F-test (Y) χ(1)2 1.0 2.0 1.0 0.03114 0.00568 0.00067
F-test (Blom) χ(1)2 0.96098¥ 0.87231¥ 0.65804¥
Welch test (Y) χ(1)2 0.05264 0.01136 0.00145
Welch test (Blom) χ(1)2 0.96551¥ 0.88077¥ 0.66728¥
F-test (Y) Weibull (1, 0.5) 1.0 2.0 1.0 0.03460 0.00808 0.00100
F-test (Blom) Weibull (1, 0.5) 0.99982¥ 0.99750¥ 0.98304¥
Welch test (Y) Weibull (1, 0.5) 0.05359 0.01076 0.00091
Welch test (Blom) Weibull (1, 0.5) 0.99985¥ 0.99775¥ 0.98388¥

Note: 100,000 simulations

¥

Indicates significantly greater than nominal α level at the 95% confidence level