Blau, David M. (1999). The Effect of Child Care Characteristics on Child Development. Journal of Human Resources, 34(4)
The effect of group size, staff-child ratio, training, and other characteristics of child care on child development is estimated using data from the National Longitudinal Survey of Youth. In contrast to most previous research, the sample is large and nationally representative, the data contain good measures of the home environment, and there are repeated measures of child development. Child care characteristics have little association with child development on average. Associations are found for some groups of children, but they are as likely to be of the "wrong" sign as they are to be of the sign predicted by developmental psychologists.
Journal of Human Resources
Blau, David M.