This paper uses the data on child development collected around the evaluation of a nursery program to estimate the details of the process of human development. We model development as made of three latent factors, reflecting health, cognitive and socio-emotional skills. We observe children from age 1 to age 7. We assume that, at each age, these factors interact among themselves and with a variety of other inputs to determine the level of development at following ages. Relative to other studies, the richness of the data we use allows us to: (i) let the dynamics be rich and flexible; (ii) let each factors play a role in the production of any other factor; (iii) estimate age-specific functional forms; (iv) treated parental investment as an endogenous input. We find that the dynamics of the process can be richer than usually assumed, which has important implications for the degree of persistence of different inputs in time. Persistence also changes with age. This has important implications for the targeting of investment and interventions, and the identification of windows of opportunities. The endogeneity of investment is also important.
