BusinessWeek – We invest in stocks — and other markets — based on an idea we pioneered called fundamental indexing. Instead of weighting companies in an index according to their market capitalization, we weight them according to how big they are as a business, by measures such as aggregate profits, sales, and dividends. The size of the company’s business becomes your anchor. So when a stock soars and its business doesn’t, trim it. When a stock plunges and its business doesn’t, buy it.