Dynamic treatment effect analysis of TV effects on child cognitive development

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.

Media and Human Capital Development: Can Video Game Playing Make You Smarter?

“…Reading should improve children's reading recognition skills. Computer use may have positive affect both types of cognitive skills and television may improve reading skills (Fiorini 2010; Malamud and Pop-Eleches, 2011; Beuermann et al, 2013; Gentzkow and Shapiro, 2008; Huang and Lee, 2010). Some active leisure activities, for example, team sports and educational games, may also positively affect cognitive skills.…”

“…According to the findings of Fiorini (2010), Malamud and Pop-Eleches (2011), and Beuermann et al (2013),computer use fosters verbal and non-verbal intelligence. Gentzkow and Shapiro (2008) and Huang and Lee (2010) conclude that moderate television watching improves children's reading ability.…”

Zero‐inflated Endogenous Count in Censored Model: Effects of Informal Family Care on Formal Health Care

“…Because 1 À g h θ 1 > 1, the sign of g à y depends on the sign of g h θ 2 + g y that consists of the direct effect g y of y 2 on y 1 and the 'indirect effect' g h θ 2 < 0 through the improved health; see Huang and Lee (2010) and Lee and Huang (2012) for this type of decomposition of a total effect into the direct and indirect effects. Because 1 À g h θ 1 > 1, the sign of g à y depends on the sign of g h θ 2 + g y that consists of the direct effect g y of y 2 on y 1 and the 'indirect effect' g h θ 2 < 0 through the improved health; see Huang and Lee (2010) and Lee and Huang (2012) for this type of decomposition of a total effect into the direct and indirect effects.…”

Finding Dynamic Treatment Effects Under Anticipation: The Effects of Spanking on Behaviour

“…Huang and Lee (2010) also showed that the G ‐algorithm reduces to the above total effect under conditions (a) and (b). The linear model assumption is critical for this, as well as for the decomposition of the total effect into the direct and indirect effects.…”

“…Huang and Lee (2010) showed that this holds if for which the above conditions (a) and (b) are sufficient. This kind of ‘selection‐on‐observables’ condition is pervasive in the literature, and it is also called ‘conditional independence’ or ‘ignorability’.…”