The standard theory that the first-best tax on pollution is equal to marginal environmental damages has been extended in two directions. First, many polluting activities are difficult to tax because they are not market transactions, and so recent papers have shown that the same effects can be...

Building on the existing literature that examines the extent of redistribution in the Social Security system as a whole, this paper focuses more specifically on how Social Security affects the poor. This question is important because a Social Security program that reduces overall inequality by...