No abstract

We investigate whether TV watching at ages 6-7 and 8-9 affects cognitive development measured by math and reading scores at ages 8-9 using a rich childhood longitudinal sample from NLSY79. Dynamic panel data models are estimated to handle the unobserved child-specific factor, endogeneity of TV watching, and dynamic nature of the causal relation. A special emphasis is put on the last aspect where TV watching affects cognitive development which in turn affects the future TV watching. When this feedback occurs, it is not straightforward to identify and estimate the TV effect. We adopt estimation methods available in the biostatistics literature which can deal with the feedback feature; we also apply the "standard" econometric panel data IV approaches. Overall, for math score at ages 8-9, we find that watching TV for more than two hours per day during ages 6-9 has a negative total effect mostly due to a large negative effect of TV watching at the younger ages 6-7. For reading score, there are evidences that TV watching between 2-4 hours per day has a positive effect whereas the effect is negative outside this range. In both cases, however, the effect magnitudes are economically small.

Parental involvement in marriage matchmaking may distort the optimal spouse choice because parents are willing to substitute love for money. The rationale is that the joint income of married children can be shared among extended family members more easily than mutual attraction felt by the couple themselves, and as a result, the best spouse candidate in the parents' eyes can differ from what is optimal to the individual, even though parents are altruistic and care dearly about their children's welfare. We find supporting evidence for this prediction using a unique sample of urban couples in China in the early 1990s.

Much evidence suggests individuals di¤er in their predisposition to cooperate, which is essentially a component of human capital. This paper examines the role of individual cooperative tendencies and their interactions with institutions in generating social trust; it also endogenizes cooperative tendencies using a human capital investment model. Multiple equilibria and ine¢ ciencies exist due to positive externalities. An innovative …nding is that, when institutions are more e¤ective in punishing defecting behaviors, more people invest in cooperative tendencies and hence the endogenous social trust is higher, though the equilibrium cooperative tendencies are lower. This paper provides a plausible explanation for many empirical and experimental results. (JEL: Z13, J24)

, and participants at the Chicago-Renmin symposium on family and labor economics at the University of Chicago, the symposium of the 80th birthday of Steven Cheung at Shenzhen, U. of Maryland workshop, the AEA meetings, the PAA conference, and the Asian Conference on Applied Micro-Economics/Econometrics at Tokyo for constructive comment and suggestions. We are especially grateful to the late Gary Becker for his detailed comments at the Chicago-Remin symposium in which we presented an earlier version of a related paper. He encouragedųs to consider the issues from the perspective of parents and old age support. This paper would not exist without his encouragement and comments. We also thank the excellent research assistance from Lixin Tang. Huang gratefully acknowledges the financial support of SMU Research Grant 10-C244-SMU-002. The views expressed here do not implicate the World Bank or the countries that it represents. Part of the paper was revised when Jin visits the Federal Trade Commission. Any view expressed here does not represent the view of the Commission, any of its commissioners, or the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peer-reviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.