The expectation that an index fund will get EXACTLY the return of the target index sets the stage for an interesting problem: Zero tracking error is achievable, but it comes at a very high price.

FORBES: Getting Over Index Investing With A Better Way

Particularly at this point in the cycle, replicating the index closes off entire sets of opportunities to investors, inhibits diversification and may magnify risks.

FORBES: With Bond Yields So Low, Why Should You Pay More For Active Management?

The exclusion of financials sets the index apart, as does the inclusion of companies that are not US-based (the Dow Jones Industrial Average for instance only covers companies based in the United States).

FORBES: MAT's Strong Dividend History Helps it Reach 'Top Dividend Stock of the Nasdaq 100'

Here's how it works: Researchers give people working in pairs three sets of 12 questions written on index cards.

WSJ: Advice for Making New Friends: Share But Don't Overshare

The shifts in these ecosystem boundaries provide an index of global climate change, which can be observed and compared in all continents of the world, using standard sets of climatic measurements, such as precipitation and temperature.

UNESCO: 83e