Knowledge that Transforms

This paper analyzes the relationship between maternal labor supply and children's cognitive development, using a sample of three- and four-year-old children of female respondents from the 1986 National Longitudinal Surveys Youth Cohort (NLSY). Respondents in the NLSY were aged 21 to 29 in 1986; thus our sample consists of children of relatively young mothers. We show that for this group the impact of maternal labor supply depends upon when it occurs. Maternal employment is found to have a negative impact when it occurs during the first year of the child's life and a potentially offsetting positive effect when it occurs during the second and subsequent years. We find some evidence that boys are more sensitive to maternal labor supply than girls though the gender difference is not significant. The negative first-year effect is not mitigated to any great extent by the increased maternal income that accompanies it, though the increase in maternal income does appears to play an important role in producing the positive effect in the second and later years.

The comovement between exports and productivity observed in many countries suggests a direct link between these two variables. This paper tries to establish whether such a causal link exists for four developed market economies, using co-integration and Granger-causality techniques. These techniques offer a means to overcome serious problems encountered in previous attempts to examine this relationship, while recent trade theory suggests that the relationship between trade and productivity is fundamentally ambiguous. Both reasons call for more empirical evidence. The findings of the econometric analysis suggest that exports, productivity and the terms of trade move together in the long run in all countries except the United Kingdom.

What accounts for the apparent preference of firms to finance investment with internal funds? Recent theories stress information problems in capital markets, while older theories emphas ize the transactions costs of external finance. To test these competing hypotheses, the authors estimate the sensitivity of investment spend ing to internal funds across firms likely to face varying degrees of information problems and transactions costs. Several attributes are used to differentiate these firms. The results provide some support for information asymmetries as well as a source of the financing hierarc hy but indicate no significant role for transactions costs.

This paper seeks to understand the recent history of U.S. external imbalances by identifying the "long-run tendency" of the U.S. current account balance and investigating its behavior. The procedure that is adopted is to estimate cointegrating regressions between U.S. exports and imports of goods and services. Estimates from cointegrating regressions between several measures of U.S. exports and imports show that up to about the end of 1983 the U.S. current account tended toward zero. Since that time, there has been an apparent structural shift resulting in a long-run tendency for a deficit in excess of $100 billion per year.

This paper shows that yields to maturity of U.S. Treasury bills are cointegrated, and that during periods when the Federal Reserve specifically targeted short-term interest rates, the spreads between yields of different maturity define the cointegrating vectors.This cointegrating relationship implies that a single non-stationary common factor underlies the time series behavior of each yield to maturity and that risk premia are stationary.An error correction model which uses spreads as Ihe error correction terms is unstable over the Federal Reserve's policy regime changes, but a model using post 1982 data is stable and is shown to be useful for forecasting changes in yields.

The effect of child-care costs on the probability that married women with children will participate in the labor market is examined. Child-care costs are estimated.using a generalized Tobit specification corrected for selection. Estimates of a structural probit model of labor-force participation provide evidence to support the prediction that increased child-care costs lower the probability of participation. It is also shown that the lower rate of labor-force participation among mothers of preschoolers is entirely the result of the higher child-care costs faced by these women and endogeneity of the number of young children in the participation equation.

This paper models the selection of environmental policies under authoritarian and democratic regimes, and tests the hypothesis that political institutions systematically affect the enactment of environmental regulations. The results support the contention that political institutional arrangements, rather than resource endowments, largely determine policies concerning environmental regulation.

The surge of interest in intergenerational transfers in the past decade has sparked a debate over the motivation for them. Are transfers given out of altruism or part of an exchange? While each motive is probably at work to some extent, they know little about whether one motive predominates. The question is relevant for issues concerning public income redistribution and inequality in the family but despite its importance, empirical evidence about motives is scarce because of limited data. They investigate a new data set, the National Survey of Families and Households, which remedies many of the shortcomings of other data sets containing private transfer information. They find that empirical patterns for inter-vivos transfers (i.e., transfers between living persons) are more consistent with exchange than altruism.