An index fund puts a constraint on itself.
指数基金对自身施加了一种限制。
I won’ to track the performance of an index and constraints come at an economic cost.
它必须追踪指数的表现，而这种限制会带来经济成本。
Well, if you’re an index fund manager, and let’s suppose they add a stock today, you’re going to add that stock in at night’s closing price.
假设你是指数基金经理，今天指数新增了一支股票，你必须在当天收盘价买入这支股票。
The most recent evidence we’ve come up with is on average that pushes up the price that stock 4% beyond what the fair price is.
我们最新的研究数据显示，这种操作平均会使该股票价格高出合理价4%。
people are fooled that they’re not paying a trading cost.
投资者误以为他们没有支付交易成本。
Because you’re buying it tonight’s closing price, but that price is 4% too high and tomorrow when trades happen, you know it changes back or proud to say we’re passive and not indexed and indexing is not bad and just it’s not great.
虽然你是以当日收盘价买入，但这个价格实际虚高了4%，次日交易发生时价格就会回调。我们可以自豪地说我们是被动投资而非指数化投资，指数化投资并非不好，只是不够出色。