> For the time being, we have to do with what we have, that is, a very diverse and heterogeneous set of data sources on wealth: historical inheritance declarations and estate tax statistics, scarce property and wealth tax data, and household surveys with self-reported data on wealth (with typically a lot of under-reporting at the top). As I make clear in the book, in the on-line appendix, and in the many technical papers I have published on this topic, one needs to make a number of adjustments to the raw data sources so as to make them more homogenous over time and across countries. I have tried in the context of this book to make the most justified choices and arbitrages about data sources and adjustments. I have no doubt that my historical data series can be improved and will be improved in the future (this is why I put everything on line).
For putting the data up online, he's proven himself to be a true scholar. This is how progress is made.
At the moment it seems to be very difficult for professional economists to come to a clear conclusion, so in terms of the academic judgement of the work, the rest of us should hardly be coming down strongly one way or another.
Edit: Ironically, there seems to be an error in the linked article:
> For America, the outcome of the analysis is relatively muddy (based in part on the fact that the source data themselves are harder to parse, according to Mr Giles). The trend for the top 1% share does not seem to be affected. For the top 10% it is harder to say; here is a chart Mr Giles produces:
When you look at the chart, it's the 10% trend (the triangles) which is unaffected, and the 1% trend (the squares) which is muddied. I therefore say with utmost confidence that I have debunked the debunking of the debunking of Piketty. I don't know which of my preconceptions that means I can keep intact.