关于reconstitute arbitrage
应该是using subjective criteria 主观评判标准更困难 这里有讲解错误
按原版书“the index rules are written so that the decision to add or remove an index constituent is voted on by a committee maintained by the index provider. Where a committee makes the final decision, the changes become difficult to guess ahead of time.”需要committee决定index个股去留，预测index成分更困难
