[thanatropism]

In Piketty's credit, he did make this easy.

Providing data for reproducibility and replicability is relatively new in economics.

There are, however, two kinds of claims here. One is that mistakes were made, which is grounds for schadenfreude for those (like me!) who don't like the slight jumps in reasoning from "inequality is rising" to "something must be done about inequality" to "this is what must be done". For all I know, the key injustice in modern economies is topocracy:

https://encrypted.google.com/url?sa=t&rct=j&q=&esrc=s&source...

But secondly, it is claimed that he cherry-picks. Economists (we) do that. A lot. And it has to be called out.

[greenyoda]

"But secondly, it is claimed that he cherry-picks. Economists (we) do that. A lot. And it has to be called out."

The total effect of his cherry picking can't even be discerned from this article. With a lot more work (more than a single blogger probably has time for), it might be shown to be much worse. For example, Piketty chose the U.K., France and Sweden for his list of European countries (averaging them all into "Europe" without adjusting for their populations, as the article pointed out). But why those particular countries? Would the results have been completely different if he would have also included Germany, one of the wealthiest and most populous European countries? We'll probably never know how he came up with his set of countries, and whether he deliberately omitted other countries whose data was available because they would have caused his results to be not significant enough to publish (or even contradicted his thesis).

This reminded me a lot of one of the original studies linking cholesterol to heart disease, which chose a carefully picked subset of European countries even though results were available for several others. Subsequent research showed that including the data from the missing countries would have yielded very different results.

[thanatropism]

Related, useful concept:

https://en.wikipedia.org/wiki/Simpson%27s_paradox

See in particular the Berkeley Gender Bias case if you don't want to hack the math apart.

The specific way you slice and dice data matters.

[Iv]

> But why those particular countries

Because they had coherent archives of several proxies that Piketty uses for a long period of time. He opened the door to people doing the same work he did and contradicting him with other countries, but I would not bash him for not doing the same work on every country on the planet.

[mchusma]

I liked your point, which is similar to my reaction to the book. Part 1: "Relative inequality is rising" Step 2: "?" Step 3: "Policy proposals"

Most notably, Piketty never made a case why his policy proposals are the best way to improve the lives of the bottom 50% on an absolute basis.

[pdabbadabba]

Have you read the book? It is clearly not his focus (or area of expertise!) but the book makes its premise clear: extreme inequality is inconsistent with the meritocratic ideals upon which modern capitalist democracies are founded, and can lead to social unrest. This is close to a direct quotation from the book's introduction --0 I would quote it exactly if I had the book in front of me right now. Maybe you don't agree with this premise, but I don't think you can fault Piketty for taking it as an assumption (explicitly!), particularly given that he is not a sociologist or political philosopher.

And in either case, it strikes me a significant contribution in itself to move the debate from "does capitalism and rising productivity raise all boats?" (answer: no) to "ok then...is extreme inequality really such a bad thing?"

[Tycho]

How is the answer to raise all boats 'no'?

[pdabbadabba]

You're right, I was imprecise. Piketty does not claim (I don't think) that capitalism doesn't raise all boats, only that capitalism and increased productivity do not raise all boats equally.