Panel A =  Teacher-rated achievement at 10 and 12 years. Panel B =  Test achievement at 10 and 12 years. Ach-Tch  =  Teacher-rated achievement; Ach-Test  =  test achievement; A =  additive genetic; C =  Shared environment; E =  Non-shared environment. The figures represent the results from a standardized Cholesky decomposition of twin data. 95% confidence intervals of the path estimates are shown in parentheses. The first factors assess genetic (A₁), shared (C₁) and non-shared environmental (E₁) influences on 10-year achievement, some of which may also influence 12- year school achievement. The second factor estimates influences on 12-year achievement that are independent of the influences on 10-year achievement (A₂, C₂ and E₂). Results indicate significant residual genetic influence on 12-year school achievement, even when the genetic and environmental co-variance with previous achievement has been removed (see the A₂ path estimate).

Panel A = g and teacher-rated achievement at 12 years. Panel B = g and test achievement at 12 years. g =  general cognitive ability; Ach-Tch  =  Teacher-rated achievement; Ach-Test  =  test achievement; A =  additive genetic; C =  Shared environment; E =  Non-shared environment. The figures represent the results from a standardized Cholesky decomposition of twin data. 95% confidence intervals of the path estimates are shown in parentheses. The first factors assess genetic (A₁), shared (C₁) and non-shared environmental (E₁) influences on g, some of which may also influence school achievement. The second factor estimates influences on achievement that are independent of the influences on g (A₂, C₂ and E₂). Results indicate significant residual genetic influence on school achievement, even when the genetic and environmental co-variance with general cognitive ability has been removed (see the A₂ path estimate).

Panel A =  Teacher-rated achievement. Panel B =  Test achievement. g =  general cognitive ability; Ach-Tch  =  Teacher-rated achievement; Ach-Test  =  test achievement; A =  additive genetic; C =  Shared environment; E =  Non-shared environment. The figures represent the results from a standardized Cholesky decomposition of twin data. 95% confidence intervals of the path estimates are shown in parentheses. The first factors assess genetic (A₁), shared (C₁) and non-shared environmental (E₁) influences on 10-year achievement, some of which may also influence g and 12-year achievement. The second factor estimates influences on 12-year g that are independent of the influences on 10-year achievement, and which may also influence 12-year achievement (A₂, C₂ and E₂). The third factor (A₃, C₃ and E₃) estimates influences on 12-year achievement that are independent of those on 10-year achievement and 12-year g. Results indicate significant residual genetic influence on school achievement, even when the genetic and environmental co-variance with previous achievement and general cognitive ability has been removed (see the A₃ path estimates).