Extract from The Economist on 'smart beta'
Step forward “smart beta”, the latest bit of jargon from the fund-management industry. “Alpha” is the skill required to choose individual assets that will outperform the market; “beta” is the return achieved from exposure to the overall market, for example via an index fund. “Smart beta” is an approach that tries to enhance the return from tracking an asset class by deviating from the traditional “cap-weighted” approach, in which investors simply buy shares or bonds in proportion to their market value.
When a company’s share price rises faster than the rest of the market, this means that it has a bigger weight in a traditional index. When its share price falls, its weight reduces. A strategy that attempts to match the cap-weighted index is thus buying high and selling low; put another way, it has a big exposure to the most expensive stocks. That makes it easier for alternative indices to outperform over the long run.
http://www.economist.com/news/finance-and-economics/21580518-terrible-name-interesting-trend-rise-smart-beta