Historical P/E ratios of small-cap vs. large-cap stocks?
There is most likely an error in the WSJ's data.  Yahoo! Finance reports the P/E on the Russell 2000 to be 15 as of 8/31/11 and S&P 500 P/E to be 13 (about the same as WSJ). Good catch, though!  E-mail WSJ, perhaps they will be grateful.
For the lazy, Wikipedia says: The term microcap stock (also micro-cap) refers to the stock of public companies in the United States which have a market capitalization of roughly $300 million or less. The shares of companies with a market capitalization of less than $50 million are typically referred to as nano-cap stocks.  Many micro-cap and nano-cap stocks are traded over-the-counter with their prices quoted on the OTCBB or the Pink Sheets. A few of the larger, more established microcaps are listed on the NASDAQ Capital Market or American Stock Exchange (AMEX).  Micro-cap and especially nano-cap stocks are notorious for their volatility. A high percentage of these companies fail to execute their business plans and go out of business. Fraud and market manipulation are not uncommon, and the transactions costs in trading can be quite high. Pricing is more likely to be inefficient, since fewer institutional investors and analysts operate in this space, due to the relatively small dollar amounts involved and the lack of liquidity. "In a cap-weighted fund, the fund itself isn't buying or selling at all (except to support redemptions or purchases of the fund). As the value of a stock in the index goes up, then its value in the fund goes up naturally. This is the advantage of a cap-weighted fund, that it doesn't have to trade (buy and sell), it just sits on the stocks. That makes a cap-weighted fund inexpensive (low trading costs) and tax-efficient (doesn't trigger capital gains due to sales). The buying high and selling low referred to by ""fundamental indexation"" advocates like Wisdom Tree is buying high and selling low on the part of the investor. That is, when you purchase the market-cap-weighted fund, at that time that you purchase, you will spend more on the higher-priced stocks, just because they account for more of the value of the fund, and less money goes to the cheaper stocks which account for less of the value of the fund. In the prospectus for a fund they should tell you which index they use, and if the prospectus doesn't describe the weighting of the index, you could do a web search for the index name and find out how that index is constructed. A market-cap-weighted fund is the standard kind of weighting which is what you get if you buy the stocks in the index and then hold them without buying or selling. Most of the famous indexes (e.g. S&P500) are cap-weighted, with the notable exception of the Dow Jones Industrial Average which is ""price-weighted"" http://en.wikipedia.org/wiki/Price-weighted_index. Price-weighting is just an archaic tradition, not something one would use for a new index design today. A fund weighted by ""fundamentals"" or equal-weighted, rather than cap-weighted, is effectively doing a kind of rebalancing, selling what's gone up to buy more of what's gone down. Rather than buying an exotic fund, you could get a similar effect by buying a balanced fund (one that mixes stocks and bonds). Then when stocks go up, your fund would sell them and buy bonds, and the fund would sell the most of the highest-market-cap stocks that make up more of the index. And vice versa of course. But the fundamental-weighted funds are fine, the more important considerations include your stocks vs. bonds percentages (asset allocation) and whether you make irrational trades instead of sticking to a plan." The value premium would state the opposite in fact if one looks at the work of Fama and French. The Investment Entertainment Pricing Theory (INEPT) shows a graph with the rates on small-cap/large-cap and growth/value combinations that may be of interest as well for another article noting the same research. Index fund advisors in Figure 9-1 shows various historical returns up to 2012 that may also be useful here for those wanting more detailed data. How to Beat the Benchmark is from 1998 that could be interesting to read about index funds and beating the index in a simpler way. "Rebalancing is, simply, a way of making sure your risk/reward level is where you want it to be. Let's say you've decided that your optimal mix is 50% stocks and 50% bonds (or 50% US stocks, 50% international, or 30/30/30 US large-cap/US small-cap/US midcap...).  So you buy $100 of each, but over time, the prices will of course fluctuate.  At the end of the year, the odds that the ratio of the value of your investments is equal to the starting ratio is nil.  So you rebalance to get your target mix again. Rebalance too often and you end up paying a lot in transaction fees.  Rebalance not often enough and you end up running outsize risk. People who tell you that you should rebalance to make money, or use ""dollar cost averaging"" or think there is any upside to rebalancing outside of risk management are making assumptions about the market (mean regressing or some such thing) that generally you should avoid." "You'll generally get a number close to market cap of a mature company if you divide profits (or more accurately its free cash flow to equity) by the cost of equity which is usually something like ~7%.    The value is meant to represent the amount of cash you'd need to generate investment income off it matching the company you're looking at. Imagine it as asking ""How much money do I need to put into the bank so that my interest income would match the profits of the company I'm looking at"". Except replace the bank with the market and other forms of investments that generate higher returns of course and that value would be lower." "ycharts.com has ""Weighted Average PE Ratio"" and a bunch of other metrics that are meant to correspond to well known stock metrics.  Other websites will have similar ratios." Yeah that all can definitely be true as well, in fact we both 100% agree on symptoms of low growth. However personally I believe there are always ways to reinvest and build your business. I mean look at AAPL, they allocated $100~ billion into their own Nevada hedge fund buying up high quality debt like it's a fire sale. Some companies create their own VC firms combatting disruptive innovation. We can argue about this all we want but share buybacks can signify a lot of things at the end of the day haha. My main point with the comment above was that the buybacks inflating EPS makes it more difficult to identify true earnings growth of a company.   So serious question, do you know of any ways to filter that out and identify real earnings growth? Small cap and mid cap shares tend to outperform large cap shares in a bull market, but they tend to underperform large cap shares in a bear market. Since the stock markets tend to go up in the long term, this suggests that a low cost small and mid cap index ETF should offer the best long term returns.   Having said that, we are currently in a mature bull market having experienced over seven years without encountering a bear market.  If a bearish outlook is something you worry about, then perhaps a broad market index, which will be heavily weighted towards large cap shares, may be a better choice for you at this time, with an eye toward switching to small and mid cap indices during the next bear market.