Speculation and Signatures(by Krugman)に関する議論の続き

Marginal Revolutionでの反応
（http://www.marginalrevolution.com/marginalrevolution/2008/06/exasperating-pa.html）

ちょっと眠いのでスミマセンが、こちらでの吉岡さんにご指摘頂いた点と同様の点をCowenも指摘しているようですね。後、在庫の話も。

The key two points in response to Krugman are: a) oil in the ground can substitute for inventories and thus speculation can be driving prices higher without it showing up in measured inventories; here's that reasoning in more detail, and b) when risk and liquidity premia are changing, the relationship between the spot price and futures price is obscure and difficult to interpret.

以上取り急ぎ。

（追記）
この件の議論の概要は、クルーグマンの最新エントリ（http://krugman.blogs.nytimes.com/2008/06/26/speculate-speculate/）をご参照ください。