Who takes care of the children? The quantity-quality model revisited

We study the Becker and Lewis (1973) quantity-quality model of children adding an explicit child care time constraint for parents. Parents can take care of the children themselves or purchase day care. Our results are: (i) If there only is own care, a quantity-quality trade-off, different from that of Becker and Lewis (1973), arises. The income effect on fertility is positive if child quantity is a closer complement than child quality to the consumption of goods. (ii) If, instead, there is a combination of purchased and own care, the effect of income on fertility is ambiguous, even if quantity of children is a normal good in the standard sense. This is the Becker and Lewis (1973) result extended to a situation with a binding child care time constraint. The conclusion is that the Becker and Lewis (1973) result holds as long as at least some child care is purchased.