Active management is a zero-sum game before cost, and the winners have to win at the expense of the losers.

The efficient market theory is one of the better models in the sense that it can be taken as true for every purpose I can think of. For investment purposes, there are very few investors that shouldn't behave as if markets are totally efficient.

An investor doesn’t have a prayer of picking a manager that can deliver true alpha.

After taking risk into account, do more managers than you’d see by chance outperform with persistence? Virtually every economist who studied this question answers with a resounding 'no.'

Active management is a zero-sum game before cost, and the winners have to win at the expense of the losers.

Markets are efficient, but there are different dimensions of risk and those lead to different dimensions of expected returns. That's what people should be concerned with in their investment decisions and not with whether they can pick stocks, pick winners and losers among the various managers delivering basically the same product.

I take the market-efficiency hypothesis to be the simple statement that security prices fully reflect all available information.