It's not saying that. The Economist refers to itself earlier¹ saying this:

> All told, Mr Piketty is guilty of sloppiness (certainly in his notation), and perhaps of some errors. But there is little evidence, so far, to support the serious charge of cherry-picking statistics. Nor have his findings that wealth concentration is, once again, rising been fatally undermined.

You claimed that he was being fraudulent, and this is saying the opposite.

¹ http://www.economist.com/news/finance-and-economics/21603022...

My article most certainly does not say that he "deliberately" altered his data, which I presume to mean towards his world view. You can't just lay out one side of the accusations then ignore the response entirely, especially when the economist is not backing up the FT's highly slanted take on it.