We wish to stress three important caveats. First, our iden- tification strategy only allows us to speak to the effects of early childhood exposure. The effects of viewing by school-age children are also clearly important for policy, and our results do not directly inform that debate. Second, we can only identify long-run effects. Although concern about the cognitive effects of early-childhood viewing has been largely motivated by the possibility of harm to long-run development, there are other potential effects of television—on violence or obesity, for example—for which con- temporaneous effects may be more relevant. .
