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. Author manuscript; available in PMC: 2014 Jun 2.
Published in final edited form as: J Speech Lang Hear Res. 2010 Jul 6;53(4):982–992. doi: 10.1044/1092-4388(2009/09-0108)

Appendix.

Model-fitting evaluation of qualitative genetic differences and quantitative differences in ACE between boys and girls

−2LL df AIC BIC DIC
Vocabulary
1. Full 25053.815 9011 7031.815 −11280.377 −17316.639
2. Fix rA 25054.111 9012 7030.111 −11282.871 −17319.803
3. Equate A 25055.511 9013 7029.511 −11284.813 −17322.415
4. Equate C 25056.316 9013 7030.316 −11284.411 −17322.012
5. Equate E 25056.684 9013 7030.684 −11284.227 −17321.828
6. Equate all 25062.501 9015 7032.501 −11286.602 −17325.543
Listening
Grammar
1. Full 23996.278 8656 6684.278 −10684.324 −16482.699
2. Fix rA 23996.684 8657 6682.684 −10686.741 −16485.786
3. Equate A 23997.487 8658 6681.487 −10688.960 −16488.675
4. Equate C 23997.089 8658 6681.089 −10689.159 −16488.873
5. Equate E 23998.270 8658 6682.270 −10688.569 −16488.283
6. Equate all 23998.500 8660 6678.500 −10693.695 −16494.749
Making
Inferences
1. Full 24778.535 8939 6900.535 −11188.897 −17176.911
2. Fix rA 24778.535 8940 6898.535 −11191.535 −17180.219
3. Equate A 24778.554 8941 6896.554 −11194.163 −17183.517
4. Equate C 24778.595 8941 6896.595 −11194.143 −17183.496
5. Equate E 24778.911 8941 6896.911 −11193.984 −17183.338
6. Equate all 24782.715 8943 6896.715 −11197.358 −17188.051
Figurative
Language
1. Full 25424.334 9274 6876.334 −11946.061 −18158.565
2. Fix rA 25424.334 9275 6874.334 −11948.720 −18161.894
3. Equate A 25424.337 9276 6872.337 −11951.377 −18165.221
4. Equate C 25424.341 9276 6872.341 −11951.375 −18165.219
5. Equate E 25424.996 9276 6872.996 −11951.048 −18164.892
6. Equate all 25425.676 9278 6869.676 −11956.025 −18171.209

Note: For all measures, 6 models were fit. Model 1: Full model, in which rA within DZO twins was allowed to fall below .5 and A, C, E parameters were allowed to differ by sex (i.e., allowing for both qualitative genetic differences and quantitative sex differences). Model 2: rA within DZO twins was set to .5; A, C, E parameters were allowed to differ by sex. Model 3: rA within DZO twins was set to .5; A parameters were equated for boys and girls but C and E parameters were allowed to differ by zygosity. Model 4: Similar to Model 3, but C parameters were equated for boys and girls. Model 5: Similar to Model 3, but E parameters were equated for boys and girls. Model 6: rA within DZO twins was set to .5; A, C and E parameters were equated for boys and girls (i.e., no qualitative or quantitative sex differences). No significant differences were obtained among the models for each measure.