Nonlinear Growth Curves in Developmental Research
Kevin J. Grimm
Nilam Ram
Fumiaki Hamagami
In the paper, the author describes several types of growth models for representing developmental theory. The paper starts with the simple linear growth curve and move toward nonlinear latent growth curves with additive and multiplicative between-person differences.
The linear growth curve (as with many growth curves) can be fit in both structural equation modeling
(SEM) and multilevel modeling frameworks.
The nonlinear latent growth curves include models of quadratic growth, latent basis growth, and a collection of additive and multiplicative nonlinear latent curve models.
One Longitudinal height study come from the Berkeley Growth Study (Bayley, 1940) and Berkeley Guidance
Study (MacFarlane, 1939) were used to demonstrate the models.
Comments:
The paper well describes the model for growth curve in developmental researcher.
I do not understand the linking from formula 5 to formula 6？