Offer your insights or judgment on the input financial query or topic using your financial expertise. Reply as normal question answering

When are equal-weighted index funds / ETFs preferable to market-cap-weighted funds?
As Dheer pointed out, the top ten mega-cap corporations account for a huge part (20%) of your "S&P 500" portfolio when weighted proportionally. This is one of the reasons why I have personally avoided the index-fund/etf craze -- I don't really need another mechanism to buy ExxonMobil, IBM and Wal-Mart on my behalf. I like the equal-weight concept -- if I'm investing in a broad sector (Large Cap companies), I want diversification across the entire sector and avoid concentration. The downside to this approach is that there will be more portfolio turnover (and expense), since you're holding more shares of the lower tranches of the index where companies are more apt to churn. (ie. #500 on the index gets replaced by an up and comer). So you're likely to have a higher expense ratio, which matters to many folks.