The Middle Ground - Competitive Markets

I don't like the terms efficiency and inefficiency. They don't seem to quite fit. We aren't talking about an internal combustion engine and we are missing the proper measuring tool, some sort of efficiency Geiger counter. I prefer the term, as suggested by Richard Roll at UCLA, "competitive". Markets are competitive. This means that prices usually indicate their true value. When they do not, as in the case of an undervalued or overvalued stock, the market, over time corrects the discrepancy. The questions then are how easy is it to find highly undervalued stock and how long it takes to correct the discrepancy. The answers are not very and your guess is as good as mine. Roll estimates that the market misprices 2% of equities. I imagine that number goes up and down depending if we are in an harem economy or a deserted island economy. With the proliferation of information through such mediums as the Internet, the markets have recently become more competitive.