Table 4 – Continuous time model parameter estimates for math and reading

Auto effect

a_reading

-4.54

1.405

a_math

-1.47

0.230

Cross effect

a_reading\(\to\)_math

1.84

0.680

a_math\(\to\)_reading

1.14

0.413

Diffusion variance

\({\sigma }_{reading}^{2}\)

5.49

1.688

\({\sigma }_{math}^{2}\)

0.91

0.093

Diffusion covariance

\({\sigma }_{reading\leftrightarrow math}^{2}\)

− 0.99

0.428

Intercepts\({t}_{0}\)

b_reading

0.27

0.014

b_math

0.28

0.014

Linear trend

tr_reading

0.25

0.002

tr_math

0.33

0.002

Variance traits

\({\psi }_{reading}\)

0.98

0.021

\({\psi }_{math}\)

1.06

0.022

Covariance traits

\({\psi }_{reading\leftrightarrow math}\)

0.86

0.019