Do changes in stock market indicators, such as the short interest ratio, signal changes in stock prices? Popular stock market lore and numerous books and articles support the worth of “technical” analysis. On the other hand, to the extent that stock prices follow a random walk, technical indicators would seem to be of no value. The two positions can be reconciled to a degree by realizing that a variable can follow a random walk with respect to its own sequence and still be successfully predicated by some other variable(s). Furthermore, successful predications of stock prices can be made on the basis of available information, if that information is used in some unique manner that has not been fully developed by other market participants.