I've been recommended these two (
one,
two) Mark Thoma posts on Alan Reynolds' views about inequality. Thoma makes several points including the important one that the Census Bureau's Current Population Survey uses $999,999 as the maximum income that can be coded so that a person making $1 million, a person making $10 million, and a person making $100 million will all register as earning $999,999. This is a serious flaw in the data's utility as a measure of inequality. He also notes that Piketty and Saez argue, in a manner that most economists seem to me to regard as perfectly credible, that "fiscal manipulation" in response to changes in the tax code could be responsible for
short-term errors in the IRS data but not for problems with the long-term trend.
This article available online at:
http://www.theatlantic.com/politics/archive/2006/12/thoma-on-reynolds-on-inequality/40998/