One of the most widely read and respected publications concerning technical analysis is a book entitled "Technical Analysis of the Financial Markets: A Comprehensive Guide to Trading Methods and Applications." A high percentage of professional traders, especially those who are technical analysts vice fundamental analysts, consider this the seminal text on the subject.
As a result, I was curious to see what this reference guide said about the importance of volume. As anyone can see below, volume is a primary confirming element of technical analysis.
Technical analysis is not an exact science, thus these patterns indicate direction and target prices not with absolute certainty, but with a degree of high probability. However, there is a danger of seeing patterns that are not there. For this reason, the use of volume as confirming the underlying market psychology is highly recommended.