How Much Has the World Changed in the Last 15 Years?

Relative mean reversion or statistical arbitrage existed in the eighties, nineties and arly two thousands because of sloppiness of a certain class of investors. As those folks evolved, that inefficiency kind of went away, and it changed so relative menrversion still exists, but it exists for a very different reason. There are a number of ways in which the landscape has shifted, really more than we have time get into now. A thereh's been a gigantic move from passive to active, ah, other way round, whow, from active to passive. And a gigantic movefrom discretion y trading interaction with the markets to algarymic interaction with the Markets.